2023 Edition
Only a licensed code officer is empowered to interpret the code. All code decisions are subject to a code officer's interpretation. An appeal can be made if the decision is questionable. Anyone can interpret the plumbing code, but the only decision which counts is the one made by a licensed code officer.
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A plumbing permit is not needed for the direct replacement of any plumbing fixture, except for a water heater. However, if a fixture location is changed, a permit is required. In other words, you can remove a toilet and replace it with a new one without the need for a permit. But, if you move the closest flange in any way, a permit is required. This is true for all plumbing fixtures.
Most alterations and repairs to existing plumbing systems are required to comply with current code requirements. There can be some exceptions to this that are available if a variance is applied for and received. An example of this could be when an existing fixture is not vented and current code requires an individual vent for the fixture. You may be able to obtain a variance from a code officer that will allow the installation of a mechanical vent instead of installing a vent pipe where it would be a hardship to do so. Minor alterations to existing plumbing have to be in compliance with current code requirements, but the existing parts of the plumbing system do not have to be changed and brought into compliance with the current code. In no case can any plumbing work cause a plumbing system to become unsafe. Making changes that are detrimental to a plumbing system are never acceptable.
Before a plumbing permit is issued a set of plans and specifications are submitted to the code enforcement office. Once they are approved, a code officer will stamp them as approved and sign them. These become the official plans and specs for a job. This being the case, a copy of the stamped and signed plans and specifications must be kept on the job site at all times for review by a plumbing inspector.
A water heater is one plumbing fixture that requires a permit and an inspection even when it is replaced in the exact location of an existing water heater. Why is this the case? Because water heaters are potential bombs. If a water heater is installed without a proper temperature-and-pressure relief valve, the pressurized vessel (the water heater) can explode due to excessive temperature or pressure.
Minor plumbing repairs do not require the issuance of a permit or an inspection. Plumbers are allowed to fix leaks, replace defective trap arms, replace faucets and similar repairs without any need for a permit. It is even permissible to replace toilets and bathing units in their exact same locations without a permit. Some states do not require a licensed plumber to make such repairs. However, if a fixture location is changed when it is replaced a permit is required.
Plumbing code regulations allow homeowners to obtain plumbing permits for work to be done on their own residences when the homeowners will do the work themselves.
Used plumbing materials can be reused under certain conditions. All materials must be of an approved type. They must be in good working order. A plumbing code officer must approve the use of the specified materials. When these conditions are met it is allowable to reuse previously used plumbing parts and fixtures
Journeyman plumbers are not allowed to apply for plumbing permits. All journeyman plumbers are required to work under the indirect supervision of a master plumber. A master plumber can obtain a plumbing permit. Homeowners who will perform their own plumbing work on their own homes are allowed to obtain permits. However, a homeowner is not allowed to obtain a plumbing permit and then allow some other person to do the plumbing work. Property owners are only allowed to be issued plumbing permits when the property where the work will be performed by the owner is the owner's personal residency. In other words, landlords are not allowed to obtain their own plumbing permits.
Most municipalities prohibit plumbers from working on municipal plumbing parts and systems. This can apply to piping, water meters, pressure-reducing valves, piping, fittings, and other devices. Normal procedure is for a plumber's work to end within a five-foot range of the foundation of a structure. There are exceptions to this rule. Any local jurisdiction can define their own rules on who may service, repair, install or remove municipal plumbing devices.
All permit applications must be accompanied by a full description of the work to be done. Larger jobs, such as plumbing a bathroom addition, a home, or a commercial building require a set of plans to be submitted with a permit application. Specifications are also required for all plumbing permits. The specs must detail all materials to be used in a job. Permit applications require the physical address of the property to receive plumbing services. Normally, the name of the property owner is also required.
Journeyman plumbers are required to work under the indirect supervision of a master plumber. Therefore, journeyman plumbers are not allowed to be self-employed plumbers. However, anyone can own and operate a plumbing business if they have a master plumber employed by the company. So a journeyman plumber could hire a master plumber and open a plumbing business. But without a master plumber, a journeyman cannot operate a full-service plumbing business. Some states do allow journeyman plumbers to work on their own in doing simple repairs and replacements that do not require the issuance of a plumbing permit.
A code officer has latitude in deciding if a permit will be rendered invalid for a lack of work being started within six months of the issuance of a permit. By code, the work must begin within the first six months of the issuance of a permit. This is the rule under both the IPC and UPC. However, you should check with your local jurisdiction, as they have authority to set their own time periods. There are times when weather or other uncontrollable issues prohibit the timely commencement of work. When this is the case a code officer can offer an extension of time for work to be begun.
Any plumbing alteration is expected to comply with current code requirements. At no time can an alteration be detrimental to a plumbing system or render the system unsafe. Some plumbers think that existing plumbing systems are exempt from current code requirements. This is true if the system is in safe operating condition. But, the moment an alteration to the system is made the alteration must be within current code requirements. However, the existing plumbing that is not being altered is not required to be upgraded to current code compliance.
Occasionally work is started on a job and then grinds to a halt. For example, the underground plumbing may be put in and the concrete contractor may delay further plumbing work. Or, the framing contractor may move slowly and prevent the plumbing contractor from moving forward quickly. Through no real fault of the plumber a job can be stalled. If plumbing work is stalled for more than six months the existing plumbing permit can be determined to be invalid. This decision is up to the local plumbing inspector.
Plumbing codes require different minimum standards for various types of building uses. For example, the minimum number of fixtures required for a building can vary substantially based on the use of a building. Accessibility requirements that do not apply to a residence can apply to an office building or business. There are several situations where everything from pipe sizing to the number of fixtures required can be different for various types of building uses. In order to change the use of a building within compliance to code requirements a plan and specifications must be submitted to the code enforcement office for approval.
Anyone may own a plumbing company provided a Master Plumber is employed by that company and has a current Master License. A homeowner is exempt from plumbing license law requirements but may have to obtain a plumbing permit to perform plumbing work on his homestead. Commercial plumbing jobs require at least a Journeyman license to perform work under the general supervision of a Master Plumber.
The authority having jurisdiction determines the provisions for licensing. State Plumbing Boards determine requirements and provide testing of qualified applicants to become licensed. Plumbing inspectors enforce codes adopted by the AHJ.
All items listed above, except estimated cost of materials are required on an approved plan. Some municipalities base plumbing permit fees on fixture units or estimated cost of total job, but not on material costs.
The most stringent provisions in any plumbing application combines all codes, standards, and manufacturer's installation instructions to ensure the health and safety of the public.
Any of these conditions can prompt the plumbing authority to order the system to be removed or placed in a safe and sanitary condition.
The plumbing authority has the power to disconnect a plumbing system from utilities in the event of an immediate hazard to life or property. The utility company can shut down the utility (i.e. natural gas), but they do not have the authority to disconnect a plumbing system. The Code states that the authority having jurisdiction shall have the authority to disconnect the plumbing system to a building, structure, or equipment regulated by the code in case of emergency, where necessary, to eliminate immediate hazard to life or property. In most scenarios, a municipality controls the water supply and the sewer to structures they supply.
Replacing a VTR and replacing it with an auto-vent would require termination and alteration of existing plumbing. A plumber may replace parts of a valve and remove and reset the same toilet without altering the existing plumbing system and all service calls are not subject to obtaining a permit.
If an employee of the plumbing authority issues a permit erroneously or has been supplied with incorrect information it may be suspended or revoked. If the person performing the plumbing work on the permitted job is not licensed, a citation may be written by a field inspector.
The code requires an air test of 10 psi to be held for a minimum of 15 minutes with no visual drop in pressure.
Mercury was formerly used in test gauges for the testing of gas systems. Because of the health risks that result from exposure to mercury poisoning, many municipalities have prohibited their use in pressure tests and relied on sensitive diaphragm gauges that require yearly certification.
All plumbing permits are required to be issued prior to any plumbing work being started. Beginning any portion of plumbing work before a permit is issued is a violation of the plumbing code. Some jurisdictions require that all permits be posted conspicuously so that they can be seen from the road or street that a property fronts on. In existing homes this is often done by posting the permit in a window where it can be seen easily by a code officer approaching the property. New construction sites often have the permits posted in weather-resistant coverings on poles or posts that are readily visible from vehicular routes.
All plumbing permits are to be signed by a licensed plumbing inspector. The signature of an inspector is the only signature required on a permit.
It is common for a code enforcement office to want a site plan and specifications on file prior to any work being done on an existing sewer or water service. The site plan should show the location of existing piping and the proposed location for new piping.
Backflow assemblies and air gaps are required by code to be inspected once a year. The devices should be tested. They must be working properly and not allowing contamination to the water source of a water distribution system. They are also required to be inspected when they are installed. If any repairs are done to the devices, a test and inspection of the repaired device must be performed. Additional devices that require this same procedure include the following: Double check valve assemblies Reduced pressure detector fire protection backflow prevention assemblies Double check detector fire protection backflow preventers Spill-proof vacuum breakers Backflow preventers on any hose connections Reduced pressure principle backflow preventer assemblies Pressure vacuum breaker assemblies
A Stop Work Order is a very serious matter. Code officers issue and post these orders only when there is an immediate danger or a possible danger pending. Minor code violations will result in a rejection from a code officer, not a Stop Work Order. When a Stop Work Order is issued or posted it must be observed immediately. In other words, stop all work instantly. Contact the issuing code officer for instructions. The code officer's name will be affixed to the Stop Work Order. If you continue to work you and your employer could find yourselves in immense trouble.
If a code enforcement officer finds conditions that may prove to be an issue for health and safety, the inspector has the authority to condemn the use of the building. This action can be appealed, but it must be accepted at the time of the posting of the notice that the building is condemned and no longer available for its previous use. The owner of the property must contact the code officer or code enforcement office to remediate the situation
Trusses are engineered. Regardless of whether they are roof trusses or floor trusses, they must not be cut, notched, drilled, spliced or otherwise altered. When truss integrity is disturbed it can lose its structural ability. Normal cutting, notching and drilling procedures associated with solid wood joists and rafters do not apply to trusses. There are, however, some occasions when a truss must be altered to allow for a plumbing installation. When this is the case, an approved engineer must provide written details on how the truss can be altered to allow for a plumbing installation. Only an engineer can do this.
Pipe protection is a major part of the plumbing trade. The code requires a minimum depth of twelve inches of compacted backfill over any buried pipe. This is used as a means of protecting the pipe. All backfill material must be clean and free of debris. For example, you cannot use backfill material that contains broken bricks, sharp rocks or other objects that may puncture a pipe. It is also important to apply backfill material in small quantities to avoid crushing a pipe or twisting a joint at a fitting. Common practice is to apply six inches of dirt and tamp it. Then another six inches of dirt is added and tamped.
Any plumbing installed in a potential flood area must be protected from the potential effects of flooding. These effects include the risk of the following: Ā Hydrostatic load and stress Ā Buoyancy Ā Hydrodynamic load and stress Ā Entry of flood water into the plumbing system
Ground corrosive effects on piping must be considered before a plumbing installation is made. If the chemical effects of the ground will compromise certain types of piping material, such as copper, protection for the piping must be put in place. This can take the form of a sleeve or a protective, approved coating on the piping. Under no circumstances shall pipe be installed in corrosive ground conditions without suitable protective measures in place.
When plumbing systems are properly protected from flooding and the design and installation meets with code enforcement approval they may be installed below a design flood elevation.
Any pipe that penetrates an exterior wall is required to be provided with adequate pipe protection. By code, adequate pipe protection is a sleeve that has a minimum diameter that is twice the diameter of the pipe it is protecting. This sleeve is required to prevent the plumbing pipe from being crushed if the exterior wall shifts on the foundation supporting it.
The depth of frost penetration in earth varies from region to region. For example, the frost line in Maine is 4 feet. In a more southern state the frost line could be 18 inches. Local plumbing codes define the depth of a frost line in their jurisdictions. Regardless of the depth of a frost line, plumbing pipes must be installed no less than 6 inches below the established frost line as determined by the local plumbing code. And, at no point is there to be less than 12 inches of ground cover over a buried pipe.
The fire resistant factor must not be compromised. Approved plans and specifications will dictate how penetrations may be made and sealed. Fire ratings will be specified. A typical allowable temperature rise is 325 degrees F above the initial temperature through the penetration on a non-fire side when tested in accordance with ASTM E 814. This is often referred to as a T rating. All fire stopping materials must be code approved.
The maximum distance between pipe supports for plastic DWV piping is four feet. Spacing of pipe supports vary depending on the type of piping being supported and the direction of installation for the piping.
There are many types of adapters that can be used for various conversions and transitions from one type of pipe to another. Male and female adapters can be used on water piping and drainage and venting piping. Compression fittings can be used on water piping and drainage and venting piping. Rubber compression sleeve adapters can be used on drainage and venting piping. Rubber insert adapters can be used to convert bell-and-spigot cast iron piping to plastic piping.
Mechanical joints are approved for joining materials of dissimilar type as well as materials of the same type.
Most plumbing pipe is associated with a grade/fall of one-quarter of an inch of fall per running foot. This is not the case with condensate piping. The amount of grade required for a condensate line is one-eighth of an inch by foot. Why is this? The line is not carrying any solid waste. Only clear water is being conveyed. This s why the amount of fall is less than what would be required for a drainage waste system.
You must follow the manufacturer's installation instructions as they are the primary requirement to observe when installing condensate disposal systems. The plumbing code does require certain piping requirements, such as the amount of grade that must be installed on a drainage pipe. The material used for drainage conveyance must also be of a material approved by the local code. However, the pivotal point of condensate piping requirements is determined by the manufacturer's installation requirements.
All equipment that emits condensate drainage is required to be equipped with a drainage system. This applies to evaporators, ice machines, cooling coils and any other type of equipment that needs to release liquid in the form of clean waste.
All auxiliary drain pans for condensate systems are to be equipped with water-level detection devices that conform to UL 508. The device must shut off any equipment served by the drain pan if an overflow of the drainage pan may occur. Consult the manufacturer's recommendations for any additional requirements that may be needed.
Materials approved for the construction of a condensate drainage system can include any of the following: Ā Galvanized Steel Ā Copper Ā PEX Ā Polyethylene Ā ABS Ā PVC Ā CPVC Ā Cast Iron
Condensate drain piping must have a minimum interior diameter of .75 or an inch. This is for a single drainage pipe. If multiple pipes are attached to the main condensate drain the minimum diameter of the arterial drain piping must be enlarged accordingly to accept the additional condensate flowage.
The plumbing code defines the minimum thickness for a number of types of materials, such as metal pans used to collect condensate drainage. Other examples pertain to lead shower bases and even tubular trap thicknesses. The minimum thickness rulings are important since they have been engineered for the purposes to which they are applied.
It is common for modern DWV systems to be tested with air. In the old days water was the most common means of testing. When there is a leak that cannot be found easily, smoke can be used to expose the leak location. Smoke is not used as a primary test method. Air is the test medium of choice. The testing of a DWV system is to be conducted for a minimum of 15 minutes. The minimum test pressure is required to be 10 pounds per square inch (PSI). If only underground plumbing is being tested there must be one riser that is at least ten feet above the main plumbing system.
All Code books refer to pipe, tubing and fittings according to inside diameter with measurements expressed in both English and Metric units.
A Journeyman plumber is not required to be under the direct supervision of a Master Plumber. It is a violation of the plumbing Code for a journeyman plumber to work under a homeowner's permit and to receive payment, for such would require a Master Plumber operating as a business and obtaining the plumbing permit.
All indirect connections require an air gap when discharging into a plumbing system. A discharge line run out to the street is not draining into a plumbing system.
Engineers specify materials that conform to standards but not all products available have been approved yet. The plumbing authority having jurisdiction may approve the use of such products and master plumbers must comply with the administrative authority's decisions.
Some pipe manufacturers list measurement in one foot increments when rolls of pipe are 100' or over, but do not list increments on joints of 21', 20' or less. Brand names, psi rating, and nominal pipe size are required.
Failure to ream or deburr pipe ends can result in all outcomes noted.
A twin ell cannot be used in a drainage system. All other fittings listed can be used in both systems.
Offset flanges are prohibited in drainage and vent systems.
Pipe sleeves are required to be 2 pipe sizes larger than pipe size installed. The other options do not allow for expansion and movement in foundation.
Pipe hangers for PEX tubing must be spaced 32" apart.
The minimum fixture requirements for a single-family home include a toilet, lavatory, bathing unit, kitchen sink, and washing machine connection. Keep in mind that these are minimums. Additional fixtures, such as hose bibs, dishwashers, additional bathroom fixtures and others could be included.
Multi-family units are not required to have an individual washing machine connection. They do require a toilet, lavatory, bathing unit and kitchen sink. A laundry connection can be required when a multi-family dwelling has 20 or more dwelling units. It is not required for individual units. The plumbing code does require one laundry connection for every 20 units in a building. In effect, a 40-unit building is required to have a minimum of 2 laundry connections.
Daycare facilities are usually required to offer one toilet for every 15 people in a daycare. Some codes require that the facilities be split into two different rooms. This can result in the need for two toilets. The required minimum fixture requirements are required to be divided evenly between bathrooms for opposite sexes. This is not always the case. Check your local code to see how it interprets a need for separate facilities.
Employees must not have to walk more than 500 feet to reach suitable restroom facilities. During this walk they are not required to ascend more than one set of steps. Bathrooms under these conditions cannot be installed more than one story above the work area. There are possible exceptions for buildings that house factory workers or industrial workers. The 500 foot rule is the typical standard, but you should check your local code to confirm the local requirements.
Hospitals are required to have a minimum of two water services in case one water service becomes unable to provide adequate water for the needs of the facility. While two separate water services are required, only one water main is required. This permits both water services to be tied into a common water main.
Accessible plumbing facilities are generally required in structures that serve the public. They are not a requirement in residential housing. By real estate standards, a multi-family housing unit is considered to be a residential facility until they exceed five rental units. Even then, accessible plumbing is rarely required in all of the rental units. However, accessible plumbing is required in hotels, motels, commercial bathrooms and similar facilities.
Drinking fountains are not allowed to be installed in public bathrooms.
Plumbers working to meet accessible requirements for plumbing facilities must be aware of both the local plumbing code and the local building code. Additionally, the height of toilets must meet minimum requirements. The point of this is that a plumber must pay attention to both the plumbing and building code when working with accessible plumbing needs. The plumbing code dictates fixtures. Requirements of the building code outline minimum spacing requirements for doors and access. In order to maximize full accessible plumbing facilities a plumber must cross over from both the plumbing and building code.
Handicap toilets are available with heights that include 16 inches, 18 inches and 20 inches. Eighteen inches is the most common height of a standard handicap toilet.
Accessible routes for travel to public restroom facilities are not allowed to pass through kitchens, storage rooms, closets or similar spaces.
There are many types of toilets available. The various types of acceptable toilets include the following: Siphon jet Siphon vortex Siphon wash Reverse trap Blowout
Handicap lavatories are required by code to have a minimum of 21 inches of clearance in front of the lavatory. They must be installed in a way to allow easy access by a person in a wheelchair. A rule of thumb measurement is to create a visual box that is 30 inches by 30 inches in front of a handicap lavatory. If someone can sit in this visual box and use the lavatory easily, the spacing is probably fine. This same rule applies to kitchen sinks.
A handicap lavatory must be installed so that there is no more than 35 inches from the top of the lavatory to the top of a finished floor. When working with accessible plumbing fixtures plumbers must remember that clearance requirements and heights are not the same as they are for typical plumbing installations. The fixtures must be installed in a way to serve the people to whom they are intended to provide plumbing resources.
The maximum height allowed for a kitchen sink is 34 inches from the top of the sink to the top of a finished floor.
The maximum length of a travel route to a unisex toilet facility is 500 feet. A unisex restroom must not be located more than one story above or below a separate-sex restroom. All unisex restroom are required to be served by an accessible route.
Lavatory faucets must be located no farther than 25 inches from the front edge of the lavatory being served by the faucet when the fixture is intended for handicap use.
The maximum operational force required to activate a handicap faucet is five pounds. Faucets must be easy to operate when used for accessible purposes. The type of handles allowed on handicap faucets may include any of the following: Blade handles Wing handles Single handles Senior-units Push-button handles
Bathtubs installed for handicap use are required to have seats and grab bars. The grab bars are to have a minimum diameter of 1.25 inches and not more than 1.5 inches. These bars must be at least 24 inches in length. Bars are to be installed horizontally. There should be grab bars in the area of the seat provided for the bathing unit. Design and strength requirements for grab bars are provided in the local building code. A seat for a handicap bathtub may be of an integral type or a removable type.
Hoses installed for the operation of personal shower units in handicap bathing units are required to have a minimum length of five feet.
A kitchen sink installation requires a minimum toe space that is at least nine inches high and nine inches deep. This can be a common element of an installation for a plumber to overlook, especially when the base cabinet is made as a custom cabinet. Production cabinets should meet minimum standards for both the building and plumbing code. But this may not be the case with a handcrafted cabinet. It is wise to check all potential code violations prior to making a plumbing installation.
A handicap shower is to have a seat that is no wider than 16 inches. The seat is to be mounted along a sidewall of the shower and it should run the full length of the shower. A height requirement for the seat requires that the seat be installed at a height of not less than 17 inches and not more than 19 inches. This height is to be measured from the finished floor.
Any lever or button that is used to control the operation of a drinking fountain is to be mounted on either the side or the front of the plumbing fixture. These are the only two locations that are acceptable.
Both toilets and bidets require a minimum open floor space of 30 inches to be installed. This is to allow a minimum of 15 inches of clear space from the center of the fixture drain to the nearest fixture, wall or obstruction. Essentially, a plumber can measure from one obstruction to another and determine if there is 30 inches between them. If there is, the center of the drain for either a toilet or bidet can be installed in the center of the space. It is not required that the fixture be centered in open space, but there must be at least 15 inches from the center of the drain to the nearest obstruction.
Plumbing inspectors can consider several factors when inspecting the installation of plumbing fixtures. Fixtures are to be installed level. They are not to be installed in a manner that makes them crooked. As an example, the tank of a toilet should have the same distance measured from the edge of the tank to the back wall on the left side that it does on the right side. Good workmanship is always a consideration in any plumbing installation. Even adequate space for proper cleaning can be considered. In the end, all fixtures must be installed in a code-compliant manner.
Toilets can have reverse traps. A blowout toilet bowl is also acceptable. Siphon jet bowls are common and a wash down toilet is fine.
Closet bolts are normally made of brass. They must be made of some type of material that is resistant to corrosive action. Otherwise the bolts will deteriorate over time and the toilet will no longer be secured to the closest flange. When a closet flange, which is recommended, is not used, the lag bolts used to secure a toilet are required to be brass or some other non-corrosive material.
The minimum unobstructed opening of egress for a shower door installed on a typical shower is 22 inches.
In this scenario you will not install any of the options offered in the question. Temperature actuated flow reduction valves are not a suitable replacement for a balanced pressure valve, a thermostatic valve or a combination shower and tub valve. The simple solution is to install an anti-scald mixing valve.
Grab bars are not allowed to be installed below faucets in bathing units. For safety reasons the code requires the bars to be installed above faucets. One reason is to discourage people from grabbing the faucet as a support device.
The device used to block the drainage opening of a bathtub can be one of any of the following: Ā Plunger stoppers Ā Rubber stoppers Ā Lift-and-turn stoppers Ā Push-pull stoppers Ā Snap-down-pop-up stoppers
If a tub waste is installed with the use of slip nuts and washers an access panel to service the tub waste is required. Solid, permanent connections for tub wastes, such as solvent-weld joints, do not require an access panel. The reason for this is that the washers used with slip-nut connections may need to be replaced from time to time. Settling of a building foundation can shift and cause slip-nut connections to leak. Therefore, anything other than permanent joints made on tub wastes require the installation of a removable access panel to allow for proper inspection and servicing.
All dishwashers are required to discharge their waste through an air gap. This is to prevent back siphonage. Without the use of an air gap there is a risk that dirty drain waste water could be sucked back into a dishwasher. This could introduce bad bacteria into the fixture. One alternative to the use of an air gap is the installation of a backflow preventer on the drainage line. However, the common installation calls for an air gap to be mounted on the deck of a kitchen sink or countertop. The dishwasher drain hose connects to one end of the air gap. A separate hose attaches to the other end of the device and conveys the waste water to the general drainage system. Since the waste passes through open air at the air gap, the risk of back siphonage is eliminated.
Water coolers are required to have the drinking delivery device located at the front of the drinking unit. When water is called for it is to flow upward for a minimum distance of four inches. Levers and buttons that are used to control the flow of water may be mounted on either the front or the side of a driving fountain.
Wastewater from a washing machine should discharge into an indirect waste receptor. What does this mean? It is not complicated. A typical installation has the discharge hose for the washing machine discharging into the open end of a two-inch drainage pipe that is trapped. Another acceptable means of discharge is for the washing machine hose to hang over the rim of a laundry sink and discharge wastewater into the trapped sink drain. This type of piping arrangement is known as an air break and it prevents back siphonage.
The minimum size of a drain pipe accepting the discharge from a garbage disposer is 1.5 inches. The connection must be a solid connection that does not use an air break or an air gap. The drainage pipe is to be trapped. Garbage disposers can be discharged into a continuous waste drain under a kitchen sink. Or, it may be trapped and discharged directly into the sanitary drainage system. Garbage disposers do require a water source, which is usually a kitchen faucet. Most garbage disposers are mounted to one of the drainage holes in a kitchen sink.
Floor drains are required to discharge into a drain pipe that has a minimum diameter of two inches. This should go without saying since the minimum diameter of a drain pipe installed below concrete is two inches. Every floor drain must be trapped and they are typically required to be provided with a vent. Removable strainers for the floor drains are also a code requirement. All removable strainers are required to be readily accessible.
All bidets are required to be protected from back siphonange. A vacuum breaker is normally used for this purpose. If a backflow preventer is not an integral part of a bidet being installed you must provide protection for the fixture in the supply piping from the water distribution system.
The minimum drain diameter for a shower drain is two inches. Bathtubs are allowed to have drains with 1.5-inch diameter drains. This is because the bathtub can retain water as it is drained. Showers do not have the high flood-level rims that bathtubs do. Because of this, they must be drained more quickly. Shower drains are to be trapped and vented. All shower drains are required to be equipped with removable strainers.
When measured from the surface of a shower drain the shower walls must extend 70 inches above the drain.
Sheet lead used for a shower pan lining must have a minimum weight of no less than four pounds per square foot. The lead is to be coated with an asphalt paint or other approved coating. The sheeting must be insulated from any conducting substances, except the drain connection. Fifteen-pound asphalt felt, or an equivalent thereof, is the normal means of insulating the sheet lead. Any sheet lead that must be joined is to be joined by burning.
Drinking fountains and water coolers must not be installed in rooms where toilet facilities exist.
Ballcock assemblies for toilets are required by code to be of an anti-siphon design. It remains possible to buy ballcocks that do not meet this criteria, but they are not approved by the plumbing code standards.
Sheet copper that is used as a liner for a shower must have a minimum weight of 12 ounces per square foot. Some suitable form of insulation is required to be applied between the sheet copper and the subflooring that exists for a shower installation. This is most often done with 15-pound asphalt felt, but the insulation can be of some other equivalent material.
Commercial garbage disposers are big beasts. They usually sit on a tripod set of legs to support their weight. A minimum diameter of a drain pipe for these machines is two inches. They require their own drainage piping and trap. Do not confuse the code regulations for residential garbage disposers with the requirement for commercial garbage disposers. A cold water source must be available to the disposer. The water source can be of an automatic type. Commercial garbage disposals are not allowed to be connected to grease interceptors.
Any piping used in conjunction with a sterilizer is required to be accessible. It is not required to be readily accessible. Remember that readily accessible means that you can see and touch the piping without removing anything. Accessible plumbing can be concealed by a removable access panel.
Garbage can washers are common commercial plumbing fixtures. They must be supplied with a water source and must be equipped with a backflow preventer or an air gap. Every garbage can washer is required to have an individual trap. Discharge from the fixture must pass through an approved, removable strainer to prevent large particles from entering a sanitary drainage system.
Urinals must be equipped with individual flush valves. A single flush valve is not allowed to operate more than one urinal.
Commercial water closets are required to have elongated bowls and elongated seats. Round-front bowls are allowed for residential use, but they are not allowed for commercial applications. Commercial toilet seats are required to be hinged and they are required to have split fronts.
Clinical sinks are also known as bedpan washers.
Sterilizers are to be connected to steam piping that is installed with a gravity system that controls condensation and prevents moisture from entering the sterilizer. Steam vapors are required to be controlled. An indirect waste connection is a requirement for the appropriate installation of a sterilizer. All sterilizers are required to have leak detectors. This type of unit is considered a special fixture.
For a plumbing system to be readily accessible, the plumbing should be able to be seen and touched without having to move, or remove, anything.
Vacuum fluid-suction systems are intended to be installed in cabinets or cavities, but they must be visible and readily accessible. When central systems are installed in hospitals they must be connected to emergency power facilities. Venting for a vacuum fluid-suction system requires that the vent extend to outside air through a pipe that penetrates the roof of a building. Any central fluid-suction system must be intended for continuous use. The cleaning and maintenance of a central fluid-suction system must not interfere with the operation of the system even when cleaning and maintenance is being provided.
Bedpan washers must be connected to a vent. The minimum diameter for such a vent is required to be two inches in diameter. Vents for bedpan washers must extend to outside air above the roof of the building that houses the fixture. The vent is needed to convey odors and vapors from the fixture to the outside air. It is a code violation for local vents, the type used for bedpan washers, to tie into vents for a sanitary drainage system or a sterilizer vent.
Backflow prevention devices must be installed at least six inches above the flood-level rim of the fixture being served. When such a device is used for a handheld shower unit the backflow preventer must be installed a minimum of six inches above the highest point that the shower can be held to.
Vacuum breakers are the most common form of backflow prevention devices used in hospital settings. Vacuum-suction systems require the installation of air gap or a vacuum breaker. Boiling-type sterilizers are required to be protected by air gaps. But in general, vacuum breakers remain the most common form of backflow prevention in hospitals.
Sensor valves are not required.
1.6 gallons per flush is the present industry standard.
The maximum distance AFF for the rim of an ADA urinal is 17".
120° is the maximum temperature allowed for a public lavatory.
The main water heater thermostat is not considered a control for meeting the provision of the Code.
Due to privacy standards and unsanitary conditions resulting from their use, trough urinals are no longer allowed to be installed in public restrooms.
The minimum clearance for a lavatory, or water closet, from the side wall or partition to its center is 15".
The clearance is measured from inside partition walls; not center of partition.
Despite the availability of brass-coated steel, nylon and plastic commode bolts on the market, brass bolts are specified by Code because of their strength and corrosion resistance.
The minimum distance between adjacent fixtures (center to center) in a public restroom, other than accessible fixtures, is 30".
Slip joints are connected using an elastomeric gasket and nut and may need to be replaced or repaired due to movement or expansion/contraction therefore needing accessibility.
A 2" diameter trap and stand pipe is required on domestic washer drain connections but branch drain pipe size must be 3" or larger to accommodate additional fixture drains on branch.
An air break allows the hose to discharge without possible spillage (as with an air gap) but protects against backflow and siphonage.
This Code requirement was removed to prevent compliance issues during inspections as some manufacturers ceased to comply by not indicating the washer conformed to ASSE 1007.
ASSE 1007 required domestic clothes washers to contain an internal air gap on the machine but manufacturers quit complying with ASSE 1007 when the requirement was dropped. It was virtually unenforceable since inspectors were unable to visually inspect the appliance without disassembly.
1.5" inside diameter pipe size is the minimum for bath tub drains.
If the waste and overflow is a slip joint type, then an access panel is needed. All tubs require an overflow to prevent flooding should the valve be left on.
An air gap at least twice the diameter of the pipe size is required to prevent back siphonage.
Code requires a water temperature limiting device conforming to ASSE 1070 or CSA B 125.3.
An air gap or a backflow preventer must be present on a bidet.
Since Code officials cannot always determine if the appliance has an internal air gap, many will require a backflow preventer to be installed.
No temperature range is specified by Code other than "tepid".
Depending on what hazardous waste or contaminants may be introduced into the building sewer, the building owner may have to contain and dispose of these wastes under a different regulatory authority.
To achieve ease of rodding out trap and drain, at least a 2" pipe size is needed.
An air gap is the most common and effective means to prevent backflow.
Cold water keeps greases more solid for better grinding results.
34" is the maximum acceptable rim height for an ADA lavatory.
1.25" and 1.5" are used for trapping lavatories.
Public restrooms seldom have water heaters dedicated for their use, so a tempering device is required.
Due to unsanitary and privacy issues, trough urinals are no longer Code approved.
Drains from washing machines are required to discharge into an indirect-waste receptor. This is required to prevent contaminated water from entering a potable water source. This is accomplished by a trapped and vented indirect-waste receptor. The discharge hose from the clothes washer is inserted into the standpipe of the receptor and does not come into contact with drainage water in the trap.
Standard practice is to trap the drain of an indirect waste if the drainage pipe will extend more than two feet in length. Some local code jurisdictions may not require a trap until the extended length of the drain exceeds five feet. Check your local rules and regulations to be certain on this point. P-traps are the most common type of trap used in modern plumbing applications. Keep in mind that the trap will have to be fitted with a receptor to receive waste from some piping operations. In other cases a simple floor drain can serve as a receptor, but the drain must be trapped and a vent is normally required for every trap installed.
A building cannot have a combined system. Two separate systems are required. Special wastes cannot be allowed to enter a sanitary drainage system until it has been treated and confirmed to offer no risk to a typical sanitary drainage system.
An air gap is believed to be superior to an air break for the protection of an indirect wastepipe from back siphonage. Due to the nature of installation there is more risk of a backflow occurring with an air break. Since air breaks have discharge piping entering a receptor it is feasible to have the sanitary drain become clogged and back up, which could result in contaminated waste traveling back to the indirect waste fixture. This is not possible when an air gap is used.
Traps are not allowed to be installed on the discharge piping from relief valves that serve water heaters, boilers or expansion tanks installed in conjunction with boilers. These types of discharges are clear water and do not contain waste or fecal material. Sewer gas is not transported through these discharge outlets. In all of the cases above, the wastes are to terminate above a floor or over an indirect waste receptor, such as a floor drain. Therefore, they cannot be trapped.
The discharge tubing, hose or piping being conveyed to an indirect waste receptor is never to enter the trap seal. This defeats the entire purpose of the air break. Once the tubing, hose or pipe is in the drainage, water held in the trap there is high risk of potential backflow to the fixture that the indirect waste is serving.
The standpipe receptor that will receive the discharge from a clothes washer must be at least 18 inches tall and not more than 42 inches tall. The measurement is made from the trap seal, not the top of the trap. The receptor must also be accessible. In other words, it cannot be concealed in a finished wall that does not allow for access.
A drain that collects the waste from an independent drain for a clothes washing machine must have a minimum diameter of three inches. Pipe with a 2-inch diameter can convey the waste from the trapped receptor at the washing machine to the branch drain or drain stack where it terminates.
Wye-branch tailpieces can be installed between a kitchen sink basket strainer and the trap serving the sink when a discharge port is required for the hose that extends from an air gap that is serving a dishwasher drain.
Indirect wastes are generally not approved for use in rooms that contain toilets. There can be special exceptions when licensed code enforcement officers authorize such a change. One such exception is most commonly the approval for the installation of an indirect waste receptor for an automatic clothes washer. But most installations do not use an indirect waste receptor in any room that houses a toilet.
Indirect waste receptors are not to be installed in closets or unvented areas. All indirect waste receptors are required to be accessible.
In this scenario, it is required that the floor drains connect to the drainage system through an air gap. However, there could be an exception. When a system is protected from backflow by a backwater valve it may be permissible to make connections between a floor drain and a sanitary drainage system with an air break. Keep in mind that we are talking about a situation when the floor drain is in a walk-in refrigerator or freezer. Waste receptors can sometimes be the hub of a pipe that extends one inch above a water-impervious floor. When this is the case a strainer is not required on the pipe. Due to potential tripping hazards, most plumbers would opt to make their connections through air gaps.
Commercial dishwashing machines are allowed to use high-temperature hot water. This is water that is in excess of 140 degrees F. When the temperature of hot water will exceed 140 degrees the discharge from the dishwasher must discharge through either an air gap or an air break. Then it must be received by a standpipe made of approved materials for the high-temperature water. In the case of steam pipes, they are not allowed to be connected to a sanitary drainage system. Check your local code requirements to confirm what types of materials must be used to accommodate high-temperature water. You may find that you will have to install special piping, a sump or a condenser.
All of the above locations can require the installation of special waste piping and systems. A special waste is one that may have a harmful effect on a plumbing or waste disposal system. The use of strong chemicals is one reason why special waste piping systems are required. Bio-hazardous waste is another reason for the need to provide a system for special waste. Special waste must be neutralized, diluted or otherwise treated before it can be allowed to enter a sanitary drainage system. Small, personal photography laboratories are rarely required to be equipped with piping for special waste.
Clear water waste from a potable water system is to be piped to an indirect waste and must discharge through an air gap. This is as simple as having the discharge pipe terminate six inches above the strainer of a floor drain.
Plumbing vents server multiple purposes. Their primary purpose is to keep sewer gas from entering a building's enclosed air. This is done in two ways. The first is that sewer gas is vented out of a plumbing system by a vent and the gas is emitted into open air outside of the building where the plumbing is installed. By preventing plumbing traps from being siphoned dry vents prevent sewer gas from entering buildings through unprotected traps. A side benefit of vent installation is that the drains being served by the vent will drain faster as a result of air admittance into the drain.
Combination-waste-and vent (CWV) systems do not require independent vents on all fixtures. Instead of a vertical vent the fixtures approved for a CWV installation are installed with oversized drains. Due to the larger drain diameter the fixture obtains the needed air for drainage in the top section of the oversized piping. Urinals, toilets and bidets are not allowed to be installed on CWV systems.
You are not allowed to install bathtubs on CWV systems. Floor drains, drinking fountains and lavatories are allowed to be installed with a CWV system. So are sinks. Showers and toilets are not allowed on a CWV system. Neither are bidets or garbage disposers.
It is fine to use relief vents in conjunction with circuit vents. It is common for a relief vent to be installed near a soil stack that is accepting the waste from multiple fixtures that are being served by a circuit vent and a vent stack.
Drum traps are allowed for use in CWV systems. Since vents are not required in a CWV system, the traps used for fixtures must be of an anti-siphon type. A drum trap is such a trap.
Individual vents are allowed to be combined with other vents in a venting system when the arterial vent of the system will terminate outside of the building into open air. It is never acceptable for a vent to terminate in the attic of a building.
A relief vent can be one-half the diameter of the drain pipe being served by the vent. In this scenario each drain can be vented with a 1.5 relief vent. If one of the drains had been piped with a 4-inch diameter it would require a relief vent with a minimum diameter of two inches.
A maximum allowable grade for a horizontal drain that is circuit vented is one inch per foot.
Circuit vents are used when venting a battery of fixtures. The vents may be tied into other vents that extend to outside air. This includes vent stacks and stack vents. The diameter of a circuit vent must be at least one-half the size of the drain that it is serving.
Branch vents are vents that are installed horizontally. They act as an arterial vent that other vents can be connected to. When a branch vent is piped with piping that has the same diameter of the drain being served by the vent the branch vent may have an unlimited developed length.
Vent stacks are used only as vent pipes. They extend upward from a drainage system to open air. Other vents may be connected to vent stacks. Any vent stack is determined to be a primary vent.
Vents are required to be protected against freezing when the region of a vent installation is subject to freezing conditions. To be more specific, the ruling is usually that vents do not require freeze protection except in areas when temperatures may reach a low of zero degrees F. One way of fighting freezing conditions is to expand the pipe sizing for a vent. As an example, a 3-inch vent is considered unlikely to freeze as a result of condensation and freezing temperatures that reach a level of zero degrees F. If this over sizing method is used, the increased vent sizing must apply to all exterior vents and at least one foot inside of the building housing the vent.
Vents stacks are allowed only to be used as a vent. Stack vents and wet vents are allowed to be used as both drains and vents. Offsets installed in stack vents must not be made until the stack vent rises to a level that is at least six inches above the flood-level rim of the highest fixture being served.
Common vents are restricted to use only for fixtures that are located on the same floor level. When fixtures are at different floor levels a single common vent cannot be used. An additional common requirement is that a common vent shall not serve more than two traps. However, some local codes may allow up to three traps for lavatories to be vented by a common vent.
The only fixtures allowed to be vented with island vents are sinks and lavatories. When an island vent is installed it must rise to the highest point possible in a cabinet. Even though the plumbing is called an island vent it is treated as a drain since it does not rise above the flood-level rim of the fixture being served. The vent portion of the piping is required to contain a cleanout. Connecting an island vent to a general venting system is allowed once the island vent rises a minimum of six inches above the flood-level rim of the fixture being served by the vent. The vents are rarely used. Their most common use is in kitchens where sinks are installed in island cabinets.
Stack vents must rise a minimum of six inches above the flood-level rim of the highest fixture being served before it can be offset with fittings.
Wet vents serve as a vent for one fixture and a drain for a different fixture when the two fixtures exist in the same bathroom group if the wet vent is providing a horizontal branch drain. Fixtures must discharge downstream of the wet vent. A benefit to using wet vents is reduced cost in both the labor and material required to provide a plumbing installation. When a wet vent is used a vertical vent for a fixture is eliminated. Vertical wet vents can be used to vent any combination of fixtures within two bathroom groups located on the same floor level.
Crown-vented traps are not allowed in modern plumbing systems. However, crown vents can be used, but they must be installed on trap arms and not on traps. If a crown vent is installed on a trap arm, it must be installed at a point that is at least twice as far from the trap as the diameter of the trap arm. As an example, you have a 1.5-inch trap arm - a crown vent installed on it must be at least three inches away from the trap. The crown vent will be downstream of the trap it is serving.
Sumps for sewage pumps that remove sanitary waste are required to be vented to outside air. The vent cannot be tied into a general venting system if a pneumatic sewer ejector pump is to be installed. When a typical sewer pump is to be used the vent can tie back into a general venting system. Generally, the minimum diameter of a vent for a sewage sump will be required to be two inches in diameter. In addition to proper venting, sewage sumps must be equipped with gas-tight covers.
It is common for stack vents to be connected to drainage stacks at intervals of every five stories. These connections must be made with a relief yoke vent. This vent must be at least as large as the soil stack that it is connected to. And, the connection point is required to be a minimum of 42 inches above floor level. There are some variations on this rule with local codes, so check your local code book to confirm the requirements in your region.
The minimum allowable diameter for a main vent is three inches. The code requires a main vent to be no smaller than one half the diameter of the building drain. But at the same time it requires that the smallest diameter allowed for a main vent is three inches. So, up to a building drain with a diameter of six inches you must install a main vent with a diameter of no less than three inches. One exception is the requirement for main vents in detached buildings that contain only a washing machine or laundry tub. When this is the case the minimum allowable diameter of a vent pipe is 1.5 inches.
It is not acceptable to risk having sewer gas enter open windows. With this in mind, vents that are within 10 feet of windows must extend a minimum of two feet above the window. The two options are to keep vents at least 10 vent away from windows or extend them to two feet above the windows.
Some codes require buildings that have soil stacks with more than five branch intervals to be equipped with vent stacks. These vent stacks are usually installed close to a soil stack. You may find that the vent stack must be installed within 10 times its pipe size on the downward side of a soil stack. Given this factor, a 3-inch vent stack would have to be within 30 inches of a soil stack.
Cleanouts are required during the installation of a sewer when the sewer connects to a building drain. Any change in direction in excess of a 45-degree bend requires the installation of a cleanout in sewer piping. The normal spacing of cleanouts in straight runs of a sewer pipe is 100 feet. There are exceptions to these rules, but the information here is the typical installation requirement for cleanouts associated with sewer piping.
The cleanouts used at the junction of a building drain and sewer can usually be installed on either side of the foundation between the two pipes. Most plumbers, real estate developers and builders prefer the cleanout to be installed outside of the foundation wall. In the case of a serious sewage backup this keeps the cleanout opening outside of the structure being served. In the event that a cleanout for a sewer connecting to a building drain is to be made inside the foundation, a plumber may be required to extend the riser of the cleanout pipe to a point above the flood-level rim of fixtures being served by a horizontal drain.
Cleanouts are not required when a drain pipe makes a turn of no more than 45 degrees. The fact that three 45-degree fittings are used to make an offset is not reason to require the installation of a cleanout.
Due to the large diameters of these sewers the cleanouts may be spaced up to 400 feet apart. They are still required at points of changes in direction. When manholes are used for access to large sewers the manholes and their covers must be of approved types. All sewer cleanouts are required to be accessible. This is accomplished by installing a riser from the sewer to approximately ground level for the finished grade. The cleanout fitting is then installed on the riser pipe.
Drain pipes with diameters of four inches, or less, are required to have cleanouts installed at a maximum distance of 50 feet apart. In our example this requires two cleanouts for this rule. A cleanout is also required when the pipe changes direction with an angle greater than 45 degrees. Since this pipe installation has a 90-degree bend another cleanout is required. Therefore, a total of three cleanouts are required.
A cleanout installed in a building drain that has a minimum diameter of three inches can eliminate the need for a junction cleanout between the building drain and the sewer. However, the cleanout on the building drain must be located no more than 10 feet from the junction point.
Cleanouts are required at the end of all horizontal drain runs. There are some cases where a cleanout is not required if the developed length of a drain is less than 100 feet. However, this is not the normal case. Every horizontal drain should have a cleanout installed when it turns to a horizontal run. This is usually done with the installation of a combination fitting that is also known as a T-Y fitting with the cleanout fitting in the end of it.
Fittings housing cleanout plugs are not allowed to be used as a connection point for a drainage pipe that will serve a new fixture, unless the connection is approved by a code officer and a new cleanout is provided to replace the cleanout being changed over to a connection point for drainage piping.
Approved two-way cleanouts are allowed at the junction of building drains and sewers. But, they are not the only type allowed. Any type of approved cleanout can be used. These types could be any of the following: Ā Rubber caps that are installed with stainless steel clamps Ā Female adapters fitting with cleanout plugs Ā Test tees are suitable cleanouts Ā Special cleanouts that allow the cleaning of a drain in both directions, upstream and downstream, are acceptable.
Cleanouts are not required when horizontal drains are located above the first floor of a structure. They are still a good idea when they can be accessible, but they are not required. Sink drains that run less than five feet in length do not require cleanouts. A change in direction from a vertical drain with a fifth-bend does not require a cleanout. Also be aware that water closets are considered to be a viable cleanout and the same is true of P traps. So, if a drain terminates upstream at a P trap or toilet, a cleanout is not required.
Cleanouts are required to be accessible. Adequate space in front of the cleanout is required for effective drain cleaning. Fittings installed to accept a cleanout must be installed with the same direction of flow that is being used for the drain that the cleanout serves. The size or required cleanouts is determined by the diameter of the pipe being served. Pipes under the diameter of four inches require cleanouts equal to the diameter of the pipe being served. Larger drains can usually be served by cleanouts with 4-inch diameters.
When practical, cleanouts for under-floor piping should be installed at a height that is 18-48 inches above the finished floor level. This is not always practical. An example could be a grocery store where the building is large and requires cleanouts throughout travel paths. When this is the case, the cleanout can be installed flush with the finished floor. It must not be equipped with a raised-head cleanout plug. A sunken-head cap must be used to remove tripping hazards.
Cleanouts can be installed below floor level. However, they must be installed no more than 20 feet from an access opening. This normally pertains to cleanouts installed in basements and crawlspaces.
Several devices can be considered to be acceptable cleanouts. These devices include the following: Ā "U" bends of P traps Ā Water closets Ā Rubber caps that are installed with stainless steel clamps Ā Female adapters fitting with cleanout plugs Ā Test tees are suitable cleanouts. Special cleanouts that allow the cleaning of a drain in both directions, upstream and downstream, are acceptable.
The minimum required distance in front of a 3-inch cleanout is 18 inches. Drains with smaller diameters require a minimum open distance of 12 inches. This space is needed to allow for successful drain cleaning methods. Never point a cleanout towards a floor or wall without adequate space being provided.
When a sewer has a diameter that exceeds 8 to 10 inches a manhole is normally used as a cleanout. When this is the case most jurisdictions require the manholes to be located at maximum intervals of no more than 300-400 feet. The manholes must be protected from flooding. Covers used on manholes must allow gases from the sewer to escape to open air. Flexible compression connections are normally used to install manholes. The connections must not be closer than one foot to a manhole and not more than three feet away from a manhole.
Trap seals are required to have a minimum depth of two inches and a maximum depth of four inches. Special circumstances can alter these figures, but they must be approved by a code officer. If a trap seal is subject to going dry as a result of evaporation a trap primer must be installed to ensure a continuous liquid trap seal.
Any plug used for a cleanout must be made from either plastic or brass material. These are the only materials approved by the plumbing code for the construction of cleanout plugs. The plugs must be durable and strong enough to be removed throughout the life of the plumbing system.
P traps are required to be vented properly to avoid the risk of the trap seal being removed by backpressure. If the trap seal is removed harmful sewer gas can infiltrate interior air space in a structure. This can result in both annoying smells and potential health hazards. Since P traps are self-cleaning traps the trap seal can be siphoned out of the traps if a vent is not installed to protect the trap seal.
P traps are the modern plumbing trap of preference. S traps are still in use in older buildings, as are many other types of traps, but they are not approved for new installations. Other types of traps that are no longer allowed in new plumbing installations include the following: Crown-vented traps House traps Running traps Bell traps Drum traps, except when they are used as a part of a combination-waste-and-vent plumbing system Traps that depend on moving parts or interior partitions
No plumbing fixture is allowed to be double trapped.
The maximum allowable length for a tailpiece between a fixture and its trap is 24 inches. Why is this important? The first reason is that it is a code requirement. When a tailpiece is too long it allows a straight drop from a fixture to its trap that may result in splash back. When this happens, solids in the drain waste can hit the bottom of a trap and bounce back up the tailpiece. In some cases the result can be solid waste clinging to the tailpiece. In some cases, such as a toile installation, the waste may collect under the water closet and contribute to an eventual stoppage that will require drain cleaning. Therefore, the vertical drop is limited to 24 inches.
Grease traps are required to be fitted with devices that control water flow. The maximum water flow must not exceed the rating given for the grease trap being protected. If water flow exceeds the maximum flow rate, the performance of a grease trap can suffer and result in an inadequate trapping of grease materials.
Dishwashers are allowed to discharge through kitchen sinks. Clothes washers are not. A clothes washer can discharge into a laundry sink or a service sink or a dedicated indirect waste, but it must not discharge into a kitchen sink.
P traps that use solvent-weld joints, or other suitable permanent joints, may be used below grade for concrete slabs. No easy access is required for these traps. Situations when such traps will be used include floor drains and shower drains. It is not acceptable to use traps that rely on slip nuts and washers for a trap connection to drainage piping. Since bathtub traps cannot be connected until after a concrete floor is poured, cured and present, a tub box (also known as a trap box) must be provided. This box makes the under-floor piping accessible for an above-grade connection, which can be made with slip nuts and washers. However, solvent-weld P traps are most commonly used for this purpose. The tub box must be protected from water, insect and rodent infiltration.
Grease traps are actually not traps at all. Yes, they are called grease traps. But, they are actually grease interceptors. They are typically installed in building uses other than residential dwellings. The purpose of the device is to retain grease that would otherwise clog drains, sewers and waste-treatment facilities. They can be small or large. Grease traps must be accessible for cleaning.
Interceptors in a plumbing system are designed to control grease, sand, oil and other materials. Sand interceptors are required to be readily accessible. A sand interceptor requires a water seal that is at least six inches deep. Not all interceptors are the same. For example, and interceptor used for a commercial laundry facility is not required to have a liquid trap seal. These devices can use wire to limit the introduction of lint, string and other objects into a drainage system. This is not to say that the indirect waste receptor for automatic clothes washing machines are not required to be trapped with P traps that are vented and that retain a liquid trap seal.
It would be a code violation to install a 2-inch trap on a laundry sink that is piped with a minimum-diameter trap arm. The trap arm size would be 1.5 inches. You cannot install a trap that has a larger diameter than the drain that is serving a fixture. It would be fine to install a 1.5 inch trap on a lavatory that has a 1.25 tailpiece and a 1.5 drain. If the laundry sink had a 2-inch drain, you could use a 2-inch trap. But, you cannot install a 2-inch trap on a 1.5 inch drain.
In essence, you can take the total flow-through rating based on GPM and determine grease retention capacity, in pounds, buy doubling the flow-throw rating. In this case the rating for flow-through is 12 GPM. That allows for 24 pounds of grease. If the flow-through was 15 GPM, the grease trap would be allowed to hold up to 30 pounds of grease. You can find a sizing chart in your local code book that will show this factor clearly. Total Flow-Through Rating in GPM Grease Retention Capacity in Pounds 7 14 10 20 15 30 18 36 25 50 50 100 100 200
Oil separators are required equipment at several types of establishments. The type of use of the facility dictates the need for an oil separator. Examples of the types of building uses that require oil separators include the following: Ā Auto repair garages Ā Gasoline stations equipped with grease racks Ā Grease pits Ā Work racks for automotive repair Ā Car-washing facilities Ā Factories where oil-bearing, grease-bearing, and flammable wastes may enter the building's drainage system
Backwater valves are installed on drains and sewers. They act as something of a check valve to keep downstream waste from entering the drainage system that the backwater valve is protecting. These devices prohibit sewers from backing up into building drains. A backwater valve must be installed in such a way to make it readily accessible.
The plumbing code prohibits food waste grinders from accepting the following types of waste: Ā Emulsifiers Ā Chemicals Ā Enzymes Ā Bacteria
Standpipes installed to collect the waste from clothes washers are required to have a minimum height of 18 inches and a maximum height of 42 inches. Some local code requirements may have exceptions to this rule, but the information here is the normal code requirement.
A three-bowl kitchen sink can be plumbed with a continuous waste that collects discharge from all three sink bowls and dumps the waste into a single trap. The trap must be vented. When a single trap is used for a three-bowl kitchen sink, the trap must be in a location that is central to all three of the sink bowls.
Trap installations must not be crooked. If the trap seal is not level it can be at risk of siphonage which would result in the loss of the trap seal. A trap that is extremely crooked may not have the minimum 2-inch trap seal of liquid that is required. Workmanship is always a factor in a plumbing installation.
Cleanouts installed in the bases of plumbing stacks must not be more than 48 inches above the level of a finished floor. This is meant to allow for suitable drain cleaning. A higher elevation would make it difficult to use large drain-cleaning equipment.
Only potable water is allowed to be used for drinking, cooking and bathing. Gray water and non-potable water can be used for flushing toilets and urinals.
The primary piping that delivers potable water to a water-distribution system is called either a water main or a water supply. This is the case whether the water is coming from a water well or a municipal water system. The minimum diameter for a water supply pipe is .75 inch.
Water services and sewers can share a common trench. They must be separated. This is normally done with a stable shelf, usually made of dirt, that provides a solid platform for the installation of the water service. When this is done the water service must be at least 12 inches above the sewer. If this is not practical, the two pipes can be installed on the same level as long as the two pipes are spaced a minimum of five feet apart and separated by undisturbed or compacted earth between the two. An exception is that a water service can be installed across a sewer if the water service piping is sleeved for at least five feet horizontally from the sewer pipe centerline on both sides of the crossing.
Any waste from a reverse osmosis system entering a sanitary drainage system must pass through an air gap or an air-gap device. The function of a reverse osmosis system is converting non-potable water to potable water. Therefore, the waste is required to pass an air gap or air-gap device as it enters a sanitary drainage system.
Water service piping is not allowed to be installed above, through or under a septic system or other waste disposal system. This regulation is in place to prevent the potable water supply from being contaminated by waste should piping be compromised.
A water service pipe must be protected from freezing by being buried below the local frost line. The pipe is also required to be protected from flooding to prevent floating. When backfilling a ditch that contains a water service the backfill must be clean and free of sharp objects to protect the piping from damage that may be caused under the weight of backfill material and settlement movement.
Water service piping that is not rated for water distribution use must be changed over to water distribution pipe at, or before, the full-open valve that is required at the entrance of the water service pipe into the building. A rule of thumb is that the water service pipe should never proceed more than five feet within a building before it is converted to water distribution piping.
Insulating blankets that can be bought and installed on water heaters to increase efficiency are not required by the plumbing code. However, all water heaters are required to be insulated. The amount of insulation required is determined based on heat loss from the unit within a one-hour period of time. Manufacturers insulate water heaters and the amount of insulation must be approved for use before the water heaters are installed. For a common-sense approach, it is safe to assume that water heaters available commercially for sale in a state are approved for installation in the state where they are being sold.
All flexible water connections are required to be accessible. This means that they can be concealed in a cabinet or behind an access panel, but they must be accessible.
Water hammer is the action known to cause piping to bang. One cause of water hammer are long, straight runs of water piping. This can be avoided by installing offsets in long runs of water piping. Added protection can be provided with air chambers that are installed above water outlets. Quick-closing valves, such as those used in washing machines and ballcocks, are known to cause water hammer. Air chambers are the best defense against a water hammer which is usually annoying and can be harmful to piping. When pipes are vibrating their joints can be weakened.
When the water pressure being supplied to a residence exceeds 80 psi a pressure reducing valve is required to reduce the pressure to a point at or below 80 psi. The valve must be installed near the point of entry for the water service pipe.
Double-check valves can be used to control backflow when they are equipped with an approved vent. You do not have to vent double-check valves in every installation. However, if the valve is being used as a form of backflow prevention the check valve is required to be vented.
Booster pumps can be installed to increase water pressure as needed. These pumps are installed as a part of the water distribution system. These pumps are capable of reducing volume to increase pressure without negative effects on the performance of plumbing fixtures.
Water storage tanks are not allowed to be installed beneath soil or waste pipes. The tanks must be protected from contamination. If the tank is of a gravity type it must be equipped with overflow provisions. Any water supply to a water storage tank is required to be automatically controlled. Inlet water is to enter through an air gap that is at least four inches above the overflow for the tank. Every tank must be capable of being drained and equipped with a drain valve to prevent unwanted draining.
A diaphragm-type pressure tank is required to be equipped with a relief valve that is rated for the requirements of the manufacturer's rating of the tank. The valve is to be installed on either the incoming water supply or on the tank itself. Normally, this valve is installed on a tank tee that accepts the incoming water, connects to the tank and distributes water to the water distribution system. Discharge from a relief valve is not allowed to be piped into a sanitary drainage system. Normally there is no discharge tube required for a relief valve that is installed in conjunction with a pressure tank for potable water. However, the valve must be installed in such a way to discharge safely by gravity to a suitable disposal location, which could be a basement floor.
Lawn sprinklers and irrigation systems must be installed with a form of backflow protection. Vacuum breakers are normally used. Other types of approved backflow protection can be used, but it is recommended that vacuum breakers be installed on the systems.
Pipe hangers cannot be used if they will create corrosive reactions. As an example, you should use plastic, copper or some other type of hanger that is properly coated to prevent corrosion when supporting copper tubing and piping.
Galvanized steel pipe straps are not an acceptable means of support for copper tubing or piping. The contact between the two dissimilar types of metal could result in corrosion.
Copper water tubing and piping used for water distribution that is installed horizontally must be supported at intervals not to exceed six feet. See the list below for all of the requirements for maximum support spacing for different types of water distribution piping in most jurisdictions: Ā CPVC 3 feet Ā Copper 6 feet Ā PEX 32 inches Ā Brass 10 feet Ā Galvanized steel 12 feet
Shower valves installed for use in gang showers are required to either be controlled by thermostatic means or a pressure-balance valve. This requirement is in place to prevent the scalding of people using the showers. The requirement for this type of valve is being extended to other uses and some local jurisdictions require them even in residential dwellings. Even when the valves are not required, they are a good idea. The very young and the elderly are at high risk of being scalded when water temperature changes quickly. They simply cannot react quickly enough to turn off the water or to get out of the flow.
Barometric loops are required to extend to a minimum height of 35 feet. They can only be used as a vacuum breaker. How do they work? The loop works because it rises to a height that is high enough to prevent a vacuum suction.
All sill cocks installed are required to be equipped with cutoff valves. They are also required to be fitted with a backflow preventer. These fixtures must be securely attached.
Both gate valves and ball valves are known as full-open valves. When they are open, the pipe that they are installed on has a full flow since the valve does not restrict the flow diameter of a pipe when it is completely open. Stop and waste valves are an example of a valve that restricts flow.
Gate and ball valves do not depend on rubber washers to create a positive seal.
Full-open valves are not required to be installed for every plumbing fixture. However, every fixture is required to have some type of cutoff valve. Ball valves and gate valves are required on all water heaters, between water services and water distribution piping, on the discharge piping of water supply tanks and similar locations.
Water wells are required to be installed no closer than 100 feet from a pasture. This is to keep runoff from the pasture from contaminating the water well.
All plumbing fixtures must be equipped with an approved cutoff valve. These valves can include the following: Ā Supply stops Ā Stop valves Ā Stop and waste valves Ā Gate valves Ā Ball valves
Backflow preventers installed on potable water systems are required to be inspected periodically and the devices must be accessible. Any relief port on a backflow preventer is required to have a discharge tube that is not trapped, does not enter the sanitary drainage system and that is piped to a safe and suitable disposal location.
A water service pipe must not be installed closer than 100 feet from a barnyard. It must also be a minimum of 25 feet away from a farm silo. Protection of water service piping from contamination is a high priority. You can find tables in your code book that will outline other examples of spacing requirements for water service piping. Keep in mind that the pipe delivering water from a well to a building is considered to be a water service.
Vacuum breakers are normally used to protect water heaters, sill cocks and hose bibs from backflow dangers.
Grouting installed for the protection of a well casing must be installed to a point that is at least 10 feet below ground level or that is installed to a depth where it meets solid bedrock.
Potable water delivery systems for lavatories, bathtubs, drinking fountains, sinks, showers and laundry tubs are required to be protected from backflow with an air gap. This is why the flood-level rim of these fixtures is well below the outlet of the faucet or valve delivering potable water to the fixture. Many plumbers don't think of this as an air gap protection, but it is.
An air gap is the most effective form of backflow protection. This is because when an air gap is used, water never comes into contact with a potable water system. Therefore, it is a positive means of backflow protection.
If the carbonator is not equipped with an approved internal backflow preventer you may install a vented backflow preventer that is not affected by carbon dioxide gas. Most carbonators will come equipped with an approved, manufacturer-installed backflow prevention device.
Reduced-pressure-principal backflow preventers are required for connections between potable and non-potable water sources. This is often the case when potable water is used in conjunction with automatic fire-suppression systems, such as sprinkler systems. Other types of backflow protection are available for use when fire-control systems are pressurized.
Pipe that delivers hot water is required to maintain the desired water temperature for a minimum point of at least 100 feet from the fixture being served. If this is not feasible with a typical installation there should be a recirculation pump installed. This pump will keep the hot water moving to maintain the desired temperature at the prescribed distance required.
Water-well pumps installed in basements are required to be elevated a minimum of 18 inches above the basement floor. This is an effort to protect the pump from flooding in the basement.
Hot water is to be supplied to the left-hand side of plumbing faucets and mixing valves. One exception is the use of single-handle valves. When a single-handled faucet is used, the hot water should be piped to the left side and may rely on distinct markings on the face of the faucet to define the proper position to receive hot water.
Hot water is required to be provided to fixtures that are used for cooking, bathing, washing, cleaning, laundry and building maintenance. It is not required for other fixtures.
Boiler drains and hose bibs used for connections with water supply hoses for automatic clothes washing machines require backflow prevention. This can be accomplished with valves that have integral backflow preventers or with screw-on backflow prevention devices. If screw-on devices are used, they must be installed in a permanent manner that will not allow for them to be removed from the threaded connection.
Potable water systems must be protected from contamination. This includes fitting systems that are under continuous pressure and that contain chemical additives or antifreeze with adequate backflow protection.
The pressure setting for a common water heater is not to exceed the tank and water heater manufacturer's rated working pressure. Under some codes, like the IPC, the pressure setting cannot exceed 150 degrees in any case. Normally the maximum working pressure for a water heater is 125 psi. You can determine the maximum working pressure by checking an identification marking on the water heater. The maximum working pressure is to be indelibly stamped onto the metal of the fixture or otherwise permanently attached.
Private water sources can take the form of any of the following: Dug wells Driven wells Bored wells Drilled wells Cisterns Springs Streams Reservoirs When any of these sources are used for a private water supply, the water supplied must meet minimum standards for the water supply to be potable water. This may require treatment or disinfection prior to being provided to a water distribution system.
Private water sources that are closer than 50 feet to an underground sewage disposal field are not allowed to provide water for potable-water usage. All private water sources should be located above and upstream from any possible contaminating source, which could include a septic field.
Pex tubing used to make connections with water heaters must not be installed closer than 18 inches to the connection point. This means that some other type of piping, such as copper tubing, should be installed from the connection points on the water heater and extend a minimum of 18 inches before they are converted to PEX tubing.
All piping used as a conduit for the blow-off from relief valves on water heaters are required to sustain temperatures of up to 210 degrees F.
All vacuum breakers for hose connections in healthcare and laboratory areas are required to be installed a minimum of six feet above the finished floor.
The amount of grade, also referred to as pitch or fall, for a drain pipe is determined by the size of the drain pipe. Master plumbers and other design professional establish these elements of a plumbing system based on the minimum standards required by local code requirements. As a general rule-of thumb, the proper amount of grade for a drain up to 4-inches in diameter is .25 inch per liner foot.
A fixture that requires a 2-inch trap will have a fixture-unit rating of three fixture units. Tables in the plumbing code allow plumbers in the field to quickly determine this type of conversion and evaluation.
Horizontal branches are drain pipes that branch off of a plumbing stack. They normally run in a horizontal position. However, they can turn to a vertical rise and still be considered horizontal branches.
Pipes with diameters of between three and six inches are allowed to be installed with .125 inch of grade. Even though this grade is allowable, most plumbers install pipes up to four inches in diameter with a grade of .25. When space is at a premium the smaller amount of grade can be used.
The only allowable connection between sections of asbestos-cement pipe is one that is made with a sleeve coupling of the same composition as the pipe and sealed with an elastomeric ring.
Underground piping can be joined in a number of ways, depending on the type of pipe being installed. When mechanical joints are used they are required to have elastomeric seals. Plastic piping is normally connected with solvent-weld joints, but they can be joined by other means, such as rubber couplings that are held in place with stainless-steel clamps. Cast-iron pipe that is of the bell-and-spigot type can be caulked with okum and lead. In reality, caulked joints are rarely used in modern plumbing installations. Rubber insert connectors are far more common for bell-and-spigot cast-iron pipe. The key is to match a suitable connector to the type of pipe being installed.
The normal maximum length allowed for a stub-out for a fixture is 24 inches. Clean-out extensions are not affected by this rule. If there is an unusual reason that requires a stub-out that is longer than two feet, it is possible to have a code officer approve the additional length.
Horizontal branches that connect to the bases of stacks are required to be no closer than 10 pipe diameters from the stack. All connections are required to be made on the downstream side of a stack.
Vents for vertical offsets are not required where a stack and its offset is sized as a building drain. It is normal for vent pipes to have a diameter that is smaller than the drain that they serve. However, if the vent has the same diameter of the drain it is serving it is exempt from certain vent regulations. In this case, that means that vents with diameters equal to the drains being served are exempt from the venting of vertical offsets.
A lead bend is required to have a minimum wall thickness of .125 inch. This minimum thickness requirement also applies to the wall thickness of lead traps. Neither of these items are common in modern plumbing, but the code does still regulate the devices and you may be tested on it.
A vent is required for a stack that has a horizontal offsets that is located more than four branch intervals below the top of the stack.
When drainage piping is installed exposed in a food service area it must not be installed above any working areas, storage areas or eating surfaces. Since the piping is exposed it could leak onto these areas and contaminate them. The rule applies only to exposed piping.
It is common to use mechanical joints to connect pipes of different types of materials. Both compression joints and mechanical-sealing devices are approved for use. Mechanical joints are sometimes restricted on drain pipes installed above grade. However, if the piping is accessible, mechanical joints for above-ground drains are normally acceptable. All mechanical joints are required to have approved elastomeric seals.
Drainage pumps are required to be equipped with both check valves and full-open valves. Both devices must be accessible. The full-open valve shall be installed on the discharge side of the check valve. This allows the pump and check valve to be removed without the waste in the drain pipe running back to the point of connection. Full-open valves should be installed above the cover of a sewage sump that contains a pump. When this is not possible, the valve is to be installed outside of the sewage sump in an access pit. There can be limited exceptions to this ruling. For example, a one- or two-family dwelling application may not require a full-open valve. Even if it is not required, it should be installed for servicing purposes.
Drainage piping is to be installed with the risk of flooding in mind. If an installation is being made in an area that is prone to flooding the piping must be protected. Flooding must not be allowed to float drainage piping. It is also necessary for drainage system installations to be installed so that flood water will not enter the sanitary drainage system.
The fittings allowed to change direction with horizontal piping include the following: Ā Sixteenth bend Ā Wye Ā Eighth bend Ā Sixth bend Ā Long-sweep fittings Ā Combination fittings Ā Wye with eighth bend The reason these fittings are allowed is that they have a subtle change in direction. An abrupt change in direction could result in drain blockage.
All of the listed fittings are allowed for changes in piping from a horizontal to vertical position. Additionally, any fitting allowed for changes in horizontal to horizontal direction are also approved for use when turning to a vertical position.
In order for short-sweep fittings to be used in changing direction from a vertical drain to a horizontal drain the minimum diameter of the drain must be no less than three inches. Piping with a smaller diameter is not allowed to be turned from vertical to horizontal with short-sweep fittings.
Double tee-wye or combination fittings are approved for use to collect the waste from two blowback toilets that are installed back to back on common walls. Sanitary tees are not allowed for this type of connection. Why? The long sweep of a tee-wye directs waste down, into the drainage piping. Since sanitary tees do not have the long sweep there is risk that the waste from one fixture will transfer to the base of the other fixture.
The maximum allowable distances for support hangers is determined by the type of piping being installed. When piping is being installed horizontally the maximum allowable distances between support hangers for different types of piping are as follows: Type of Piping Material Maximum Span Between Pipe Supports ABS 4 Feet PVC 4 Feet Cast Iron 5 Feet Galvanized Steel 12 Feet DWV Copper 10 feet
Flexible couplings on pipes with a diameter in excess of 4-inches that create a change in direction are required to be supported to prevent any loosening pertaining to the coupling.
Any pipe installed below grade is required to have a minimum diameter of two inches.
The maximum distance allowable between supports for vertical piping are different from some of those for horizontal piping. You can see the allowable distances between supports below: Ā ABS 4 feet Ā PVC 4 feet Ā Cast iron 15 feet Ā DWV copper 10 feet Ā Galvanized steel 15 feet
Drainage pipes installed to empty into a waste-disposal site are not allowed to be reduced in size.
Drainage pipes installed to empty into a waste-disposal site are allowed to be increased in size.
Plastic piping must be rated as Schedule 80 or greater. Normal DWV plastic piping is Schedule 40. Threading of Schedule 40 pipe is not allowed. When plastic pipe is treaded the threading must be done with dies designed for threading plastic pipe. An approved thread lubricant or tape is required to be applied to male threads only when connected threaded joints of plastic piping.
Caulked lead joints are not allowed to be painted, varnished or otherwise coated until a joint is tested and approved by a code officer. There is no code requirement that calls for caulked joints to be painted.
The plumbing code governs both medical gas systems and non-medical oxygen systems. The coverage of these elements is dealt with as special piping and storage systems or under a category of healthcare facilities and medical gas and vacuum systems. Do not confuse medical uses for non-medical uses.
Plumbing pipes and traps installed in rooms that will be used by psychiatric patient must be concealed.
Indirect waste receptors for sterilizers are not required to be trapped or vented. However, some sterilizers do require vapor vents to comply with manufacturer recommendations.
Drinking fountains installed in corridors of healthcare facilities where patients are transported by wheelchair, gurney or hospital bed must be either fully recessed or flush mounted. Normally a drinking fountain can protrude into a hallway. This is not the case in this scenario. Not only are drinking fountains required to be fully recessed or flush mounted, so are valves associated with them. In very simple terms, you cannot install drinking fountains or their valves in any way that could come into contact with equipment used to transport patients.
Fixtures and fittings used in psychiatric patient rooms are required to be vandal proof. This requirement is meant to protect patients and the plumbing system.
The plumbing code pertains to medical gases that are nonflammable. This includes such gases as those used in exhalation anesthetic systems and vacuum piping systems. These systems can be found in hospitals, dental offices and other medical facilities.
Ice makers and ice storage chests installed in healthcare facilities are to be installed in nurse stations or other areas with similar supervision. The location of ice producing and storage equipment must be protected from contamination. All ice facilities must be safe and hygienic.
Aspirators used for removing body fluids must be equipped with collection bottles or similar fluid traps.
The plumbing code does not apply to portable systems or cylinder storage in the section based on special piping and storage systems.
Indirect-waste drains that serve sterilizers are not allowed to have a developed length in excess of 8 feet (UPC) and 15 feet (IPC). Of the answer options, only 8 feet is an acceptable length. The piping must not have a smaller diameter than the size of the drain connection on the sterilizer being served. And, receptors must be located in the same room as the sterilizer that it is receiving waste from.
Not all sterilizers require vapor vents. Sterilizers that are required to have vapor vents are identified based on the manufacturer's requirements for sterilizer installation. When a vapor vent is required, it must extend independently to outside air, generally through a roof. These vents are not allowed to tie into any other venting system.
Water-supplied suction devices are required to comply with the same plumbing code requirements that pertain to aspirators.
Indirect waste piping that collects the waste from bedpan steamers must be trapped and the traps must maintain a trap seal of three inches in depth.
The plumbing code requires aspirators to discharge their waste through an air gap. A potable water supply for an aspirator is required to be equipped with a vacuum breaker or some other equivalent backflow protection.
The installation of medical gas or medical vacuum systems requires that plans and specifications be submitted to the local code enforcement officer. Further, the code officer must approve the plans and specs and issue a permit before such systems can be installed.
Medical gas and vacuum systems must be supplied with a minimum of two sources. In other words, a device that depends on bottled oxygen must be supplied with two bottles of oxygen.
A single supply pipe can be used for any number of sources of the same type.
The plumbing code recommends that sizing requirements for medical gas and vacuum systems be designed by mechanical engineers.
Water heaters must be installed in such a way that they are accessible. It is not required for the fixture to be readily accessible. Other code requirements for the installation of a water heater include that each of the following is possible with minimum effort to gain access to the fixture: Accessible for observation Accessible for maintenance Accessible for servicing Accessible for replacement
Water heaters and storage tanks for domestic hot water must have the fixture's maximum working pressure clearly and indelibly attached in a permanent manner to the fixture. This can be in the form of a metal plate that is attached to the metal tank. Any form of marking must be clear, indelible and installed for permanent placement.
The plumbing code relies on certification by third parties in the approval of water heaters suitable for use in plumbing systems. All water heaters must be installed in compliance with the plumbing code requirements. Additionally, the code demands that all installations be made in compliance with requirements set forth by the manufacturers of water heaters.
Automatic temperature controls are required on all water heaters and water heating systems for domestic hot water. This control must be adjustable and allow for the temperature setting to be set to a minimum and a maximum level. Check local code requirements to determine the maximum allowable temperature for hot water being supplied for through domestic water distribution systems.
Water heaters are permitted by code to be installed in an attic.
All electric water heaters are required to be equipped with their own electrical disconnect switch. The switch is required to be in close proximity to the water heater. When a gas-fired or oil-fired water heater is installed there must be approved cutoff valves installed on the fuel piping in close proximity to the water heater.
Valves installed on inlet piping for a water heater must be installed to serve only the water heater. Code requires that the valve be installed close to the water heater and on the same floor level that contains the water heater. It is common practice to install the supply valve within 12 to 18 inches of the water heater. The valve is not allowed to interfere with the cold water supply to the remainder of the cold water distribution system.
Vacuum breakers are required to be installed on the water supply inlet piping of all water heaters. The normal procedure for this is the installation of a tee fitting in the inlet riser. The center outlet of the tee receives a short section of horizontal pipe that is then turned in a vertical position. Another section of piping, usually about six inches in length, is installed with a female adapter on the end of it. At this point the vacuum breaker can be screwed into the female adapter.
The minimum height requirement for a water heater being installed in an attic is 30 inches. A minimum of 22 inches in width is also required. The service area surrounding the water heater is required to be level and solid. Such an installation requires open space in front of the water heater with dimensions of 30 inches deep and 30 inches wide. There must also be a clear access opening that is at least 20 inches by 30 inches for water heater removal. Additionally, an overflow pan with a drain pipe that is piped to a suitable location is routinely required when water heaters are installed above living space.
Temperature and relief valves installed on water heaters must be installed in such a way that the valve is actuated by water in the top six inches of the tank being served by the valve. It is very important to confirm that the ratings for the valve being installed are within the working limits of the water heater being protected by a valve. For example, you would not install a valve with a rating of 150 psi if a water heater was rated for a maximum pressure of 125 psi. The maximum allowable temperature setting is usually 210 degrees F.
Discharge pipes that terminate above a floor must be extended to a point of not more than six inches above the floor. The piping must be maintained so that it can flow freely on a gravity basis. It is a code violation to install a cutoff valve on a discharge tube for a relief valve. If a discharge tube is intended to discharge into a drainage system, the connection between the discharge tube and the drainage system must be made with the use of an air break. The normal size of a discharge tube for a relief valve is 0.75 inch in diameter. The discharge piping for a drainage pan that a water heater sits is in one-inch in diameter.
It is a code violation to use a relief valve in an effort to control thermal expansion. The relief valve is a safety device only and it is required to be of a self-closing type.
Discharge tubing from a relief valve on a water heater is not allowed to be trapped at all.
It is against code requirements to use threaded pipe at the terminal end of a discharge pipe for a relief valve. The reason for this is simple. If threads are present, a cap could be installed. If this were to happen the pipe would be unable to discharge. Therefore, the ends of discharge tubing and piping must not be threaded.
Safety pans for water heaters are required to have a minimum depth of 1.5 inches. The pan must be of a size that will hold the water heater being served and collect all condensate, leakage or discharge from the water heater. The pan can be made of 24-gauge metal or plastic. Drains for safety pans must extend to their point of termination with no reduction in pipe sizing. The waste from a safety pan can terminate over a suitably located indirect waste receptor or floor drain. Another option is for the piping to be extended to the outside of a building where the piping will terminate not less than six inches from ground level and not more than twenty-four inches above ground level. Discharge tubing from a relief valve is not allowed to discharge into a safety pan.
All discharge tubing installed from the relief valves of water heaters are required to be installed in a way that occupants of the building housing the water heater can observe the piping. This allows leaks from relief valves to be noticed so that proper service can be performed. When a relief valve is leaking it should be replaced.
Water is a commodity. It is in limited supply. With this in mind there is more effort being extended to allow gray water to be used for some purposes. What is gray water? It is drainage water that does not contain waste particles of a sewage nature. In an effort to conserve water, gray water may be used to flush toilet and urinals. It is also allowed to be used for subsurface landscape irrigation systems.
Dishwashers, kitchen sinks and toilets are not allowed to contribute to a gray-water drainage system. In this scenario only the bathtub can be allowed to discharge its waste into a gray-water drainage system.
All of the listed fixtures can be discharged into a gray-water holding system or drainage system. Other fixtures that are allowed to discharge into a gray-water drainage system include bathtubs and showers. The key is not to discharge a fixture that is expected to expel any solids or sewage waste into a gray-water distribution system. This removes the option for urinals, water closets, kitchen sinks and dishwashers from being used to recover gray water from in common systems.
Collection reservoirs are required to be durable, nonabsorbent and corrosion resistant--not corrosion proof. The reservoir must be closed with a gas-tight seal. An access opening is required that will allow for routine inspections to be performed.
Any gray water going into a gray-water collection reservoir is required to be filtered. This is required as a means of blocking solids from entering the collection reservoir. While the fixtures allowed for the recycling of gray water should not be transporting solids there is always a possibility the some type of solid could find its way into the drainage water. The filters stop these impurities from reaching the collection of gray water that will be recycled.
Filter media suitable for filtering gray water prior to it entering a gray-water collection reservoir includes both sand and a diatomaceous earth filter. These filters are needed to ensure that only gray water is entering the collection point for later distribution to approved uses.
The top layer over aggregate in a seepage pit or trench must be made of an approved synthetic materials or nine inches of non-compacted marsh hay or straw.
A full-open valve is required on the piping that is conveying gray water to a collection reservoir. The valve is to be installed on the downstream side of the last fixture connection to a gray-water discharge pipe. It is also required that the valve be installed prior to the discharge pipe entering a filter installed for a gray-water system that is bound for a collection reservoir.
The overflow pipe must have a minimum diameter that is equal to the discharge pipe that is emptying into a gray-water collection reservoir. An overflow pipe can be larger than the discharge pipe, but this is not a requirement. The overflow pipe is to empty into a sanitary drainage system by means of an indirect-waste connection. In addition to the overflow pipe you must install a drain pipe of the same specifications at the lowest point of the reservoir to a sanitary drainage system. One additional requirement is that the collection reservoir must be vented.
The estimation of gray water discharge is based on the gallons of use per day per occupant number based on the type of fixtures connected to a system. This is derived by use of an equation. The equation is as follows: C = A x B A = the number of occupants B = estimated flow demands per occupant C = estimated gray water discharge based on the total number of occupants
In order to establish collection systems for toilets and urinals you must consider the following: Ā Capacity Ā Coloring Ā Materials Ā Disinfection Ā Other factors
The holding capacity of a reservoir is required to be a minimum of twice the volume of water required to meet daily flushing requirements. At no time may the capacity be less than 50 gallons.
The maximum allowable time for the retention of gray water that will be used to flush toilets or urinals is 72 hours. Holding water for long periods of time can result in the growth of bacteria. This bacteria is not wanted in the plumbing system. For example, green water in a toilet tank is not appealing and could present health hazards. When a gray water recycling system is sized properly the water retained in a collection reservoir would be balanced to the fixtures served and the normal daily use of the fixtures will draw down from the reservoir often enough to avoid prolonged water storage.
It is true that the bottom of a seepage trench or bed is required to be scarified. This means, in simple terms, scratching up the ground to loosen it for absorption. Once this is done all loose material in the bottom of the trench or bed is to be removed. The end result is an earth surface that is receptive to absorbing liquids
Disinfectants allowed for the use of disinfecting gray water that will be used for the flushing of toilets or urinals may include chlorine, iodine or ozone. These are the only disinfectants identified and approved by the plumbing code.
Gray water must be dyed to be either blue or green before it can be reintroduced into a plumbing system. These are the only two colors allowed and recognized by the plumbing code.
Food-grade vegetable dye is the only type of dye that is allowed for the purpose of dying gray water prior to reuse. Other dyes are not acceptable. The reason is that the dye must do no harm when the water is reused. Since food-grade dye is safe to consume, it is safe to color gray water. Other types of dyes can contain chemicals that may harm people or the environment.
When there is a risk of inadequate gray-water supply you should plan on supplementing the gray-water with potable water. Any water supply that delivers potable water to a gray-water system must be protected by a backwater preventer. A full-open valve must also be installed on any water supply line to a gray-water collection reservoir.
The maximum allowable time for holding gray water that will be used for subsurface landscape irrigation is 24 hours. This is less than the holding time that is allowed for flushing a toilet or urinal. Why? Landscape irrigation goes directly into the surface environment. Waste from toilets and urinals go into sanitary drainage systems for wastewater treatment.
Gray water that is used for subsurface irrigation is not required to be dyed. No artificial color is required. Collection reservoirs used to collect water for subsurface landscape irrigation is not required to be fitted with a potable water source to maintain minimum capacities. Essentially, gray water used for irrigation can be used when it is available but it is not required to be available in any particular quantity.
The exact opposite is true. Such systems must be installed lower than the surface grade of any water well or reservoir. This rule applies to water sources on adjoining land. In short, the gray water cannot be used at an elevation that may allow it to disperse into potable water sources and contaminate them.
Water piping that is used to distribute gray water as recycled water to a reuse site must be identified as non-potable water in an approved manner. In all cases piping carrying gray water must be clearly identified as not being potable water.
Soil tests are required to establish perk rates for soils that will be used to house seepage trenches and beds. The testing is usually done by an engineer or an authorized public official. Local regulations vary on what designation is required for an approved perk test. Check with your local code officer to determine what agency or professional is required to conduct the testing.
Site locations for subsurface landscape irrigation systems are regulated. The regulations are set forth in the plumbing code. One example of a regulation is that all surface water is required to be diverted away from any soil absorption site.
The minimum width of a seepage trench is one foot. Seepage trenches are not allowed to have a length in excess of 100 feet. You should also know that the maximum width of a seepage trench is five feet. All trenches must be spaced a minimum of two feet apart.
Private sewage disposal systems must not be installed in compacted areas. Such areas include driveways and parking lots. It is not wise to install water pipes under compacted areas when it can be avoided, but this action is not prohibited.
Seepage beds are required to have more than one distribution pipe. All distribution pipes are to be evenly spaced with a maximum distance of five feet. What is the minimum spacing? It is three feet. There is also a requirement for there to be a minimum of one foot from the side wall to the head wall.
Seepage trenches require a minimum depth of six inches of aggregate that ranges in size from .5 to 2.5 inches in diameter. This material is to be installed below any distribution piping elevation. There is also a requirement that a minimum of two inches of aggregate be installed over the top of distribution piping.
The minimum amount of soil cover over the top of a pipe in a seepage trench is nine inches. Do not confuse this with the minimum cover requirement of general plumbing pipes that are buried, which is 12 inches.
The minimum diameter allowed for distribution piping in a seepage trench or bed is three inches.
When unions are installed on gas piping they are not allowed to be concealed. Since the joints made with unions can be loosened or taken apart, the unions must be able to be inspected and tested. Testing is normally done with a soapy solution that will bubble if there is a gas leak at a fitting.
Gas piping in not allowed to be installed in laundry chutes, dumbwaiters, air-circulating ducts or elevators. The chutes, shafts and ducts can transport gas to various locations in a building if a leak should occur. Therefore, it is inappropriate to install gas piping in a location that could distribute gas beyond the location of the leak.
Gas piping installed outdoors is required to be a minimum of 3.5 inches above the ground level. This requirement exists to reduce the risk of the piping becoming rusted due to contact with the ground. This same ruling applies to gas piping installed on a rooftop.
Non-metallic gas piping installed underground must be provided with a tracer. The tracer is usually a metal wire with a minimum conductor size of 18 AWG. Since the piping is plastic it cannot be found with metal-detecting equipment. When a wire is installed alongside the piping, the metal in the conductor can be detected to determine the piping location. The tracer should rise from each end of the piping trench to a point above ground.
Oxygen is not allowed to be used when testing a gas piping system.
Gas piping that carries wet gas is required to have drip legs installed at low points. The length of the drip leg is usually six to eight inches. All drip legs are required to be readily accessible. The purpose of the drip leg is to collect condensation that accumulates so that it is not held in the gas delivery system.
Flexible gas connectors used to connect cooking ranges to a gas delivery system are not allowed to be longer than 72 inches. Most gas appliances that use flex connections are limited to a length of 36 inches, but ranges and clothes dryers are allowed to have 72-inch connectors.
Flow controls on gas systems are installed to keep the operating pressure of the system lower than the supply pressure for the system. These devices prevent excessive pressure from the distribution system. They must be approved and suitable both the inlet and outlet gas pressure for the application. The flow controls must be readily accessible.
The maximum allowable test pressure for gas piping is 125 psig. Test pressure is not to be less than 1.5 times the proposed maximum working pressure. The minimum allowable test pressure is 3 psig.
Gas piping that is installed in a single-family home and that has a volume of less than 10 cubic feet requires a test that is sustained for a minimum of 10 minutes. Testing is not allowed to be maintained for more than 24 hours. The most common testing device used is a manometer.
The maximum allowable pressure for plastic gas piping that conveys natural gas is 100 psig.
Flexible gas connectors are normally limited to a maximum length of 36 inches. When they are used for cooking ranges and clothes dryers they can be up to 72 inches in length. These devices allow a fixture to be moved for disconnection. All flex connections should be as short as is practical. This is due to them being more vulnerable to damage than hard piping.
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