CHAPTER 29
WATER SUPPLY AND DISTRIBUTION


  • SECTION P2901
    GENERAL

    P2901.1 Potable water required.
    Dwelling units shall be supplied with potable water in the amounts and pressures specified in this chapter. Where a nonpotable water-distribution system is installed, the nonpotable system shall be identified by color marking, metal tags or other appropriate method. Where color is used for marking, purple shall be used to identify municipally reclaimed water, rainwater and graywater distribution systems. Nonpotable outlets that could inadvertently be used for drinking or domestic purposes shall be posted.

    SECTION P2902
    PROTECTION OF POTABLE WATER SUPPLY

    P2902.1 General.
    A potable water supply system shall be designed and installed as to prevent contamination from nonpotable liquids, solids or gases being introduced into the potable water supply. Connections shall not be made to a potable water supply in a manner that could contaminate the water supply or provide a cross-connection between the supply and a source of contamination except where approved methods are installed to protect the potable water supply. Cross-connections between an individual water supply and a potable public water supply shall be prohibited.

    P2902.2 Plumbing fixtures.
    The supply lines and fittings for every plumbing fixture shall be installed so as to prevent backflow. Plumbing fixture fittings shall provide backflow protection in accordance with ASME A112.18.1/CSA B125.1.

    P2902.3 Backflow protection.
    A means of protection against backflow shall be provided in accordance with Sections P2902.3.1 through P2902.3.6. Backflow prevention applications shall conform to Table P2902.3, except as specifically stated in Sections P2902.4 through P2902.5.5.

    TABLE P2902.3
    APPLICATION FOR BACKFLOW PREVENTERS

    DEVICEDEGREE OF HAZARDaAPPLICATIONbAPPLICABLE
    STANDARDS
    Air gap High or low hazardBacksiphonage or backpressureASME A112.1.2
    Air gap fittings for use with plumbing fixtures, appliances and appurtenances High or low hazardBacksiphonage or backpressureASME A112.1.3
    Antisiphon-type fill valves for gravity water closet flush tanks High hazardBacksiphonage onlyASSE 1002, CSA B125.3
    Backflow preventer with intermediate atmospheric vents Low hazardBackpressure or backsiphonage
    Sizes 1/4″ – 3/4
    ASSE 1012, CSA B64.3
    Double check backflow prevention assembly and double check fire protection backflow prevention assembly Low hazardBackpressure or backsiphonage
    Sizes 3/8″ – 16″
    ASSE 1015, AWWA C510,
    CSA B64.5, CSA B64.5.1
    Double check detector fire protection backflow prevention assemblies Low hazardBackpressure or backsiphonage
    (Fire sprinkler systems)
    Sizes 2″ – 16″
    ASSE 1048
    Dual-check-valve-type backflow preventerLow hazardBackpressure or backsiphonage
    Sizes 1/4″ – 1″
    ASSE 1024, CSA B64.6
    Hose-connection backflow preventerHigh or low hazardLow head backpressure, rated working pressure backpressure or backsiphonage Sizes 1/2″ – 1″ASSE 1052, CSA B64.2.1.1
    Hose-connection vacuum breaker High or low hazardLow head backpressure or backsiphonage Sizes 1/2″, 3/4″, 1″ASSE 1011, CSA B64.2, CSA B64.2.1
    Laboratory faucet backflow preventerHigh or low hazardLow head backpressure and backsiphonageASSE 1035, CSA B64.7
    Pipe-applied atmospheric-type vacuum breaker High or low hazardBacksiphonage only Sizes 1/4″ – 4″ASSE 1001, CSA B64.1.1
    Pressure vacuum breaker assemblyHigh or low hazardBacksiphonage only Sizes 1/2″ – 2″ASSE 1020, CSA B64.1.2
    Reduced pressure detector fire protection backflow prevention assemblies High or low hazardBacksiphonage or backpressure
    (Fire sprinkler systems)
    ASSE 1047
    Reduced pressure principle backflow prevention assembly and reduced pressure principle fire protection backflow prevention assemblyHigh or low hazardBackpressure or backsiphonage
    Sizes 3/8″ – 16″
    ASSE 1013, AWWA C511,
    CSA B64.4, CSA B64.4.1
    Spill-resistant pressure vacuum breakerHigh or low hazard Backsiphonage only Sizes 1/4″ – 2″ASSE 1056, CSA B64.1.3
    Vacuum breaker wall hydrants, frost-resistant, automatic-draining type High or low hazardLow head backpressure or backsiphonage Sizes 3/4″ – 1″ASSE 1019, CSA B64.2.2
    For SI: 1 inch = 25.4 mm.
    a. Low hazard—See Pollution (Section R202). High hazard—See Contamination (Section R202).
    b. See Backpressure (Section R202). See Backpressure, Low Head (Section R202). See Backsiphonage (Section R202).

    P2902.3.1 Air gaps.
    Air gaps shall comply with ASME A112.1.2 and air gap fittings shall comply with ASME A112.1.3. The minimum air gap shall be measured vertically from the lowest end of a water supply outlet to the flood level rim of the fixture or receptor into which such potable water outlets discharge. The minimum required air gap shall be twice the diameter of the effective opening of the outlet, but in no case less than the values specified in Table P2902.3.1. An air gap is required at the discharge point of a relief valve or piping. Air gap devices shall be incorporated in dishwashing and clothes washing appliances.

    TABLE P2902.3.1
    MINIMUM AIR GAPS

    FIXTUREMINIMUM AIR GAP
    Away from a walla
    (inches)
    Close to a wall
    (inches)
    Effective openings greater than 1 inch Two times the diameter of the
    effective opening
    Three times the diameter of the
    effective opening
    Lavatories and other fixtures with effective opening not greater than 1/2 inch in diameter 11.5
    Over-rim bath fillers and other fixtures with effective openings not greater than 1 inch in diameter 23
    Sink, laundry trays, gooseneck back faucets and other fixtures with effective openings not greater than 3/4 inch in diameter 1.52.5
    For SI: 1 inch = 25.4 mm.
    a. Applicable where walls or obstructions are spaced from the nearest inside edge of the spout opening a distance greater than three times the diameter of the effective opening for a single wall, or a distance greater than four times the diameter of the effective opening for two intersecting walls.

    P2902.3.2 Atmospheric-type vacuum breakers.
    Pipe-applied atmospheric-type vacuum breakers shall conform to ASSE 1001 or CSA B64.1.1. Hose-connection vacuum breakers shall conform to ASSE 1011, ASSE 1019, ASSE 1035, ASSE 1052, CSA B64.2, CSA B64.2.1, CSA B64.2.1.1, CSA B64.2.2 or CSA B64.7. These devices shall operate under normal atmospheric pressure when the critical level is installed at the required height.

    P2902.3.3 Backflow preventer with intermediate atmospheric vent.
    Backflow preventers with intermediate atmospheric vents shall conform to ASSE 1012 or CAN/CSA B64.3. These devices shall be permitted to be installed where subject to continuous pressure conditions. The relief opening shall discharge by air gap and shall be prevented from being submerged.

    P2902.3.4 Pressure vacuum breaker assemblies.
    Pressure vacuum breaker assemblies shall conform to ASSE 1020 or CSA B64.1.2. Spill-resistant vacuum breaker assemblies shall comply with ASSE 1056. These assemblies are designed for installation under continuous pressure conditions where the critical level is installed at the required height. Pressure vacuum breaker assemblies shall not be installed in locations where spillage could cause damage to the structure.

    P2902.3.5 Reduced pressure principle backflow prevention assemblies.
    Reduced pressure principle backflow prevention assemblies and reduced pressure principle fire protection backflow prevention assemblies shall conform to ASSE 1013, AWWA C511, CSA B64.4 or CSA B64.4.1. Reduced pressure detector fire protection backflow prevention assemblies shall conform to ASSE 1047. These devices shall be permitted to be installed where subject to continuous pressure conditions. The relief opening shall discharge by air gap and shall be prevented from being submerged.

    P2902.3.6 Double check-valve assemblies.
    Double check-valve assemblies shall conform to ASSE 1015, CSA B64.5, CSA B64.5.1 or AWWA C510. Double-detector check-valve assemblies shall conform to ASSE 1048. These devices shall be capable of operating under continuous pressure conditions.

    P2902.4 Protection of potable water outlets.
    Potable water openings and outlets shall be protected by an air gap, reduced pressure principle backflow preventer with atmospheric vent, atmospheric-type vacuum breaker, pressure-type vacuum breaker or hose connection backflow preventer.

    P2902.4.1 Fill valves.
    Flush tanks shall be equipped with an antisiphon fill valve conforming to ASSE 1002 or CSA B125.3. The fill valve backflow preventer shall be located not less than 1 inch (25 mm) above the full opening of the overflow pipe.

    P2902.4.2 Deck-mounted and integral vacuum breakers.
    Approved deck-mounted or equipment-mounted vacuum breakers and faucets with integral atmospheric vacuum breakers or spill–resistant vacuum breaker assemblies shall be installed in accordance with the manufacturer’s instructions and the requirements for labeling. The critical level of the breakers and assemblies shall be located at not less than 1 inch (25 mm) above the flood level rim.

    P2902.4.3 Hose connection.
    Sillcocks, hose bibbs, wall hydrants and other openings with a hose connection shall be protected by an atmospheric-type or pressure-type vacuum breaker or a permanently attached hose connection vacuum breaker.

    Exceptions:

    1. This section shall not apply to water heater and boiler drain valves that are provided with hose connection threads and that are intended only for tank or vessel draining.

    2. This section shall not apply to water supply valves intended for connection of clothes washing machines where backflow prevention is otherwise provided or is integral with the machine.

    P2902.5 Protection of potable water connections.
    Connections to the potable water shall conform to Sections P2902.5.1 through P2902.5.5.

    P2902.5.1 Connections to boilers.
    The potable supply to the boiler shall be equipped with a backflow preventer with an intermediate atmospheric vent complying with ASSE 1012 or CSA B64.3. Where conditioning chemicals are introduced into the system, the potable water connection shall be protected by an air gap or a reduced pressure principle backflow preventer complying with ASSE 1013, CSA B64.4 or AWWA C511.

    P2902.5.2 Heat exchangers.
    Heat exchangers using an essentially toxic transfer fluid shall be separated from the potable water by double-wall construction. An air gap open to the atmosphere shall be provided between the two walls. Heat exchangers utilizing an essentially nontoxic transfer fluid shall be permitted to be of single-wall construction.

    P2902.5.3 Lawn irrigation systems.
    The potable water supply to lawn irrigation systems shall be protected against backflow by an atmospheric vacuum breaker, a pressure vacuum breaker assembly or a reduced pressure principle backflow prevention assembly. Valves shall not be installed downstream from an atmospheric vacuum breaker. Where chemicals are introduced into the system, the potable water supply shall be protected against backflow by a reduced pressure principle backflow prevention assembly.

    P2902.5.4 Connections to automatic fire sprinkler systems.
    The potable water supply to automatic fire sprinkler shall be protected against backflow by a double check backflow prevention assembly, a double check fire protection backflow prevention assembly, a reduced pressure principle backflow prevention assembly or a reduced pressure principle fire protection backflow prevention assembly.

    Exception: Where systems are installed as a portion of the water distribution system in accordance with the requirements of this code and are not provided with a fire department connection, backflow protection for the water supply system shall not be required.

    P2902.5.4.1 Additives or nonpotable source.
    Where systems contain chemical additives or antifreeze, or where systems are connected to a nonpotable secondary water supply, the potable water supply shall be protected against backflow by a reduced pressure principle backflow prevention assembly or a reduced pressure principle fire protection backflow prevention assembly. Where chemical additives or antifreeze is added to only a portion of an automatic fire sprinkler or standpipe system, the reduced pressure principle fire protection backflow preventer shall be permitted to be located so as to isolate that portion of the system.

    P2902.5.5 Solar systems.
    The potable water supply to a solar system shall be equipped with a backflow preventer with intermediate atmospheric vent complying with ASSE 1012 or a reduced pressure principle backflow preventer complying with ASSE 1013. Where chemicals are used, the potable water supply shall be protected by a reduced pressure principle backflow preventer.

    Exception: Where all solar system piping is a part of the potable water distribution system, in accordance with the requirements of the International Plumbing Code, and all components of the piping system are listed for potable water use, cross-connection protection measures shall not be required.

    P2902.6 Location of backflow preventers.
    Access shall be provided to backflow preventers as specified by the manufacturer’s installation instructions.

    P2902.6.1 Outdoor enclosures for backflow prevention devices.
    Outdoor enclosures for backflow prevention devices shall comply with ASSE 1060.

    P2902.6.2 Protection of backflow preventers.
    Backflow preventers shall not be located in areas subject to freezing except where they can be removed by means of unions, or are protected by heat, insulation or both.

    P2902.6.3 Relief port piping.
    The termination of the piping from the relief port or air gap fitting of the backflow preventer shall discharge to an approved indirect waste receptor or to the outdoors where it will not cause damage or create a nuisance.

    SECTION P2903
    WATER-SUPPLY SYSTEM

    P2903.1 Water supply system design criteria.
    The water service and water distribution systems shall be designed and pipe sizes shall be selected such that under conditions of peak demand, the capacities at the point of outlet discharge shall not be less than shown in Table P2903.1.

    TABLE P2903.1
    REQUIRED CAPACITIES AT POINT OF OUTLET DISCHARGE

    FIXTURE AT POINT OF OUTLETFLOW RATE
    (gpm)
    FLOW
    PRESSURE
    (psi)
    Bathtub, pressure-balanced or thermostatic mixing valve420
    Bidet, thermostatic mixing220
    Dishwasher2.758
    Laundry tub48
    Lavatory28
    Shower, pressure-balancing or thermostatic mixing valve320
    Sillcock, hose bibb58
    Sink2.58
    Water closet, flushometer tank1.620
    Water closet, tank, close coupled320
    Water closet, tank, one-piece620
    For SI: 1 gallon per minute = 3.785 L/m,
    1 pound per square inch = 6.895 kPa.

    P2903.2 Maximum flow and water consumption.
    The maximum water consumption flow rates and quantities for all plumbing fixtures and fixture fittings shall be in accordance with Table P2903.2.

    TABLE P2903.2
    MAXIMUM FLOW RATES AND CONSUMPTION FOR PLUMBING
    FIXTURES AND FIXTURE FITTINGSb

    PLUMBING FIXTURE
    OR FIXTURE FITTING
    PLUMBING FIXTURE
    OR FIXTURE FITTING
    Lavatory faucet2.2 gpm at 60 psi
    Shower heada2.5 gpm at 80 psi
    Sink faucet2.2 gpm at 60 psi
    Water closet1.6 gallons per flushing cycle
    For SI: 1 gallon per minute = 3.785 L/m,
    1 pound per square inch = 6.895 kPa.
    a. A handheld shower spray is also a shower head.
    b. Consumption tolerances shall be determined from referenced standards.

    P2903.3 Minimum pressure.
    The static water pressure (as determined by the local water authority) at the building entrance for either public or private water service shall be not less than 40 psi (276 kPa).

    P2903.3.1 Maximum pressure.
    The static water pressure shall be not greater than 80 psi (551 kPa). When main pressure exceeds 80 psi (551 kPa), an approved pressure-reducing valve conforming to ASSE 1003 or CSA B356 shall be installed on the domestic water branch main or riser at the connection to the water-service pipe.

    P2903.4 Thermal expansion control.
    A means for controlling increased pressure caused by thermal expansion shall be installed where required in accordance with Sections P2903.4.1 and P2903.4.2.

    P2903.4.1 Pressure-reducing valve.
    For water service system sizes up to and including 2 inches (51 mm), a device for controlling pressure shall be installed where, because of thermal expansion, the pressure on the downstream side of a pressure-reducing valve exceeds the pressure-reducing valve setting.

    P2903.4.2 Backflow prevention device or check valve.
    Where a backflow prevention device, check valve or other device is installed on a water supply system using storage water heating equipment such that thermal expansion causes an increase in pressure, a device for controlling pressure shall be installed.

    P2903.5 Water hammer.
    The flow velocity of the water distribution system shall be controlled to reduce the possibility of water hammer. Water-hammer arrestors shall be installed in accordance with the manufacturer’s installation instructions. Water hammer arrestors shall conform to ASSE 1010.

    P2903.6 Determining water-supply fixture units.
    Supply loads in the building water-distribution system shall be determined by total load on the pipe being sized, in terms of water-supply fixture units (w.s.f.u.), as shown in Table P2903.6, and gallon per minute (gpm) flow rates [see Table P2903.6(1)]. For fixtures not listed, choose a w.s.f.u. value of a fixture with similar flow characteristics.

    TABLE P2903.6
    WATER-SUPPLY FIXTURE-UNIT VALUES FOR VARIOUS PLUMBING FIXTURES AND FIXTURE GROUPS

    TYPE OF FIXTURES OR GROUP OF FIXTURESWATER-SUPPLY FIXTURE-UNIT VALUE (w.s.f.u.)
    HotColdCombined
    Bathtub (with/without overhead shower head)1.01.01.4
    Clothes washer1.01.01.4
    Dishwasher1.41.4
    Full-bath group with bathtub (with/without shower head) or shower stall1.52.73.6
    Half-bath group (water closet and lavatory)0.52.52.6
    Hose bibb (sillcock)a2.52.5
    Kitchen group (dishwasher and sink with/without garbage grinder)1.91.02.5
    Kitchen sink 1.01.01.4
    Laundry group (clothes washer standpipe and laundry tub)1.81.82.5
    Laundry tub1.01.01.4
    Lavatory0.50.50.7
    Shower stall1.01.01.4
    Water closet (tank type)2.22.2
    For SI: 1 gallon per minute = 3.785 L/m.
    a. The fixture unit value 2.5 assumes a flow demand of 2.5 gpm, such as for an individual lawn sprinkler device. If a hose bibb/sill cock will be required to furnish a greater flow, the equivalent fixture-unit value may be obtained from this table or Table P2903.6(1).

    TABLE P2903.6(1)
    CONVERSIONS FROM WATER SUPPLY FIXTURE UNIT TO GALLON PER MINUTE FLOW RATES

    SUPPLY SYSTEMS PREDOMINANTLY FOR FLUSH TANKSSUPPLY SYSTEMS PREDOMINANTLY FOR FLUSHOMETER VALVES
    LoadDemandLoadDemand
    (Water supply fixture units)(Gallons per minute)(Cubic feet per minute)(Water supply fixture units)(Gallons per minute)(Cubic feet per minute)
    13.00.04104
    25.00.0684
    36.50.86892
    48.01.06944
    59.41.256592515.02.0052
    610.71.430376617.42.326032
    711.81.577424719.82.646364
    812.81.711104822.22.967696
    913.71.831416924.63.288528
    1014.61.9517281027.03.60936
    1115.42.0586721127.83.716304
    1216.02.138881228.63.823248
    1316.52.205721329.43.930192
    1417.02.272561430.24.037136
    1517.52.33941531.04.14408
    1618.02.906241631.84.241024
    1718.42.4597121732.64.357968
    1818.82.5131841833.44.464912
    1919.22.5666561934.24.571856
    2019.62.6201282035.04.6788

    (continued)

    TABLE P2903.6(1)—continued
    CONVERSIONS FROM WATER SUPPLY FIXTURE UNIT TO GALLON PER MINUTE FLOW RATES

    SUPPLY SYSTEMS PREDOMINANTLY FOR FLUSH TANKSSUPPLY SYSTEMS PREDOMINANTLY FOR FLUSHOMETER VALVES
    LoadDemandLoadDemand
    (Water supply fixture units)(Gallons per minute)(Cubic feet per minute)(Water supply fixture units)(Gallons per minute)(Cubic feet per minute)
    2521.52.874122538.05.07984
    3023.33.1147443042.05.61356
    3524.93.3286323544.05.88192
    4026.33.5157844046.06.14928
    4527.73.7029364548.06.41664
    5029.13.8900885050.06.684
    For SI: 1 gallon per minute = 3.785 L/m, 1 cubic foot per minute = 0.4719 L/s.

    P2903.7 Size of water-service mains, branch mains and risers.
    The size of the water service pipe shall be not less than 3/4 inch (19 mm) diameter. The size of water service mains, branch mains and risers shall be determined according to water supply demand [gpm (L/m)], available water pressure [psi (kPa)] and friction loss caused by the water meter and developed length of pipe [feet (m)], including equivalent length of fittings. The size of each water distribution system shall be determined according to design methods conforming to acceptable engineering practice, such as those methods in Appendix P and shall be approved by the code official.

    P2903.8 Gridded and parallel water distribution system manifolds.
    Hot water and cold water manifolds installed with gridded or parallel-connected individual distribution lines to each fixture or fixture fittings shall be designed in accordance with Sections P2903.8.1 through P2903.8.6.

    P2903.8.1 Sizing of manifolds.
    Manifolds shall be sized in accordance with Table P2903.8.1. Total gallons per minute is the demand for all outlets.

    TABLE P2903.8.1
    MANIFOLD SIZING

    PLASTICMETALLIC
    Nominal Size ID
    (inches)
    Maximuma
    gpm
    Nominal Size ID
    (inches)
    Maximuma
    gpm
    3/4173/411
    129120
    11/44611/431
    11/26611/244
    For SI: 1 inch = 25.4 mm, 1 gallon per minute = 3.785 L/m,
    1 foot per second = 0.3048 m/s.
    Note: See Table P2903.6(1) for w.s.f.u and Table 2903.6(1) for gallon-per-minute (gpm) flow rates.
    a. Based on velocity limitation: plastic-12 fps; metal-8 fps.

    P2903.8.2 Minimum size.
    Where the developed length of the distribution line is 60 feet (18 288 mm) or less, and the available pressure at the meter is not less than 40 pounds per square inch (276 kPa), the size of individual distribution lines shall be not less than 3/8 inch (10 mm) diameter. Certain fixtures such as one-piece water closets and whirlpool bathtubs shall require a larger size where specified by the manufacturer. If a water heater is fed from the end of a cold water manifold, the manifold shall be one size larger than the water heater feed.

    P2903.8.3 Orientation.
    Manifolds shall be permitted to be installed in a horizontal or vertical position.

    P2903.8.4 Support and protection.
    Plastic piping bundles shall be secured in accordance with the manufacturer’s instructions and supported in accordance with Section P2605. Bundles that have a change in direction equal to or greater than 45 degrees (0.79 rad) shall be protected from chafing at the point of contact with framing members by sleeving or wrapping.

    P2903.8.5 Valving.
    Fixture valves, when installed, shall be located either at the fixture or at the manifold. If valves are installed at the manifold, they shall be labeled indicating the fixture served.

    P2903.8.6 Hose bibb bleed.
    A readily accessible air bleed shall be installed in hose bibb supplies at the manifold or at the hose bibb exit point.

    P2903.9 Valves.
    Valves shall be installed in accordance with Sections P2903.9.1 through P2903.9.5.

    P2903.9.1 Service valve.
    Each dwelling unit shall be provided with an accessible main shutoff valve near the entrance of the water service. The valve shall be of a full-open type having nominal restriction to flow, with provision for drainage such as a bleed orifice or installation of a separate drain valve. Additionally, the water service shall be valved at the curb or lot line in accordance with local requirements.

    P2903.9.2 Water heater valve.
    A readily accessible full-open valve shall be installed in the cold-water supply pipe to each water heater at or near the water heater.

    P2903.9.3 Fixture valves and access.
    Valves serving individual fixtures, appliances, risers and branches shall be provided with access. An individual shutoff valve shall be required on the fixture supply pipe to each plumbing fixture other than bathtubs and showers.

    P2903.9.4 Valve requirements.
    Valves shall be of an approved type and compatible with the type of piping material installed in the system. Ball valves, gate valves, globe valves and plug valves intended to supply drinking water shall meet the requirements of NSF 61.

    P2903.9.5 Valves and outlets prohibited below grade.
    Potable water outlets and combination stop-and-waste valves shall not be installed underground or below grade. Freezeproof yard hydrants that drain the riser into the ground are considered to be stop-and-waste valves.

    Exception: Installation of freezeproof yard hydrants that drain the riser into the ground shall be permitted if the potable water supply to such hydrants is protected upstream of the hydrants in accordance with Section P2902 and the hydrants are permanently identified as nonpotable outlets by approved signage that reads as follows: “Caution, Nonpotable Water. Do Not Drink.”

    P2903.10 Hose bibb.
    Hose bibbs subject to freezing, including the “frostproof” type, shall be equipped with an accessible stop-and-waste-type valve inside the building so that they can be controlled and drained during cold periods.

    Exception: Frostproof hose bibbs installed such that the stem extends through the building insulation into an open heated or semiconditioned space need not be separately valved (see Figure P2903.10).

    FIGURE P2903.10
    TYPICAL FROSTPROOF HOSE BIBB INSTALLATION NOT REQUIRING SEPARATE VALUE

    SECTION P2904
    DWELLING UNIT FIRE SPRINKLER SYSTEMS

    P2904.1 General.
    The design and installation of residential fire sprinkler systems shall be in accordance with NFPA 13D or Section P2904, which shall be considered equivalent to NFPA 13D. Partial residential sprinkler systems shall be permitted to be installed only in buildings not required to be equipped with a residential sprinkler system. Section P2904 shall apply to stand-alone and multipurpose wet-pipe sprinkler systems that do not include the use of antifreeze. A multipurpose fire sprinkler system shall provide domestic water to both fire sprinklers and plumbing fixtures. A stand-alone sprinkler system shall be separate and independent from the water distribution system. A backflow preventer shall not be required to separate a stand-alone sprinkler system from the water distribution system.

    P2904.1.1 Required sprinkler locations.
    Sprinklers shall be installed to protect all areas of a dwelling unit.

    Exceptions:

    1. Attics, crawl spaces and normally unoccupied concealed spaces that do not contain fuel-fired appliances do not require sprinklers. In attics, crawl spaces and normally unoccupied concealed spaces that contain fuel-fired equipment, a sprinkler shall be installed above the equipment; however, sprinklers shall not be required in the remainder of the space.

    2. Clothes closets, linen closets and pantries not exceeding 24 square feet (2.2 m2) in area, with the smallest dimension not greater than 3 feet (915 mm) and having wall and ceiling surfaces of gypsum board.

    3. Bathrooms not more than 55 square feet (5.1 m2) in area.

    4. Garages; carports; exterior porches; unheated entry areas, such as mud rooms, that are adjacent to an exterior door; and similar areas.

    P2904.2 Sprinklers.
    Sprinklers shall be new listed residential sprinklers and shall be installed in accordance with the sprinkler manufacturer’s installation instructions.

    P2904.2.1 Temperature rating and separation from heat sources.
    Except as provided for in Section P2904.2.2, sprinklers shall have a temperature rating of not less than 135°F (57°C) and not more than 170°F (77°C). Sprinklers shall be separated from heat sources as required by the sprinkler manufacturer’s installation instructions.

    P2904.2.2 Intermediate temperature sprinklers.
    Sprinklers shall have an intermediate temperature rating not less than 175°F (79°C) and not more than 225°F (107°C) where installed in the following locations:

    1. Directly under skylights, where the sprinkler is exposed to direct sunlight.

    2. In attics.

    3. In concealed spaces located directly beneath a roof.

    4. Within the distance to a heat source as specified in Table P2904.2.2

    TABLE P2904.2.2
    LOCATIONS WHERE INTERMEDIATE TEMPERATURE SPRINKLERS ARE REQUIRED

    HEAT SOURCERANGE OF DISTANCE FROM HEAT SOURCE WITHIN WHICH
    INTERMEDIATE TEMPERATURE SPRINKLERS ARE REQUIREDa, b (inches)
    Fireplace, side of open or recessed fireplace 12 to 36
    Fireplace, front of recessed fireplace 36 to 60
    Coal and wood burning stove 12 to 42
    Kitchen range top 9 to 18
    Oven 9 to 18
    Vent connector or chimney connector 9 to 18
    Heating duct, not insulated 9 to 18
    Hot water pipe, not insulated 6 to 12
    Side of ceiling or wall warm air register 12 to 24
    Front of wall mounted warm air register 18 to 36
    Water heater, furnace or boiler 3 to 6
    Luminaire up to 250 watts 3 to 6
    Luminaire 250 watts up to 499 watts 6 to 12
    For SI: 1 inch = 25.4 mm.
    a. Sprinklers shall not be located at distances less than the minimum table distance unless the sprinkler listing allows a lesser distance.
    b. Distances shall be measured in a straight line from the nearest edge of the heat source to the nearest edge of the sprinkler.

    P2904.2.3 Freezing areas.
    Piping shall be protected from freezing as required by Section P2603.6. Where sprinklers are required in areas that are subject to freezing, dry-sidewall or dry-pendent sprinklers extending from a nonfreezing area into a freezing area shall be installed.

    P2904.2.4 Sprinkler coverage.
    Sprinkler coverage requirements and sprinkler obstruction requirements shall be in accordance with Sections P2904.2.4.1 and P2904.2.4.2.

    P2904.2.4.1 Coverage area limit.
    The area of coverage of a single sprinkler shall not exceed 400 square feet (37 m2) and shall be based on the sprinkler listing and the sprinkler manufacturer’s installation instructions.

    P2904.2.4.2 Obstructions to coverage.
    Sprinkler discharge shall not be blocked by obstructions unless additional sprinklers are installed to protect the obstructed area. Additional sprinklers shall not be required where the sprinkler separation from obstructions complies with either the minimum distance indicated in Figure P2904.2.4.2 or the minimum distances specified in the sprinkler manufacturer’s instructions where the manufacturer’s instructions permit a lesser distance.

    For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm.

    FIGURE P2904.2.4.2
    MINIMUM ALLOWABLE DISTANCE BETWEEN SPRINKLER AND OBSTRUCTION

    P2904.2.4.2.1 Additional requirements for pendent sprinklers.
    Pendent sprinklers within 3 feet (915 mm) of the center of a ceiling fan, surface-mounted ceiling luminaire or similar object shall be considered to be obstructed, and additional sprinklers shall be installed.

    P2904.2.4.2.2 Additional requirements for sidewall sprinklers.
    Sidewall sprinklers within 5 feet (1524 mm) of the center of a ceiling fan, surface-mounted ceiling luminaire or similar object shall be considered to be obstructed, and additional sprinklers shall be installed.

    P2904.2.5 Sprinkler installation on systems assembled with solvent cement.
    The solvent cementing of threaded adapter fittings shall be completed and threaded adapters for sprinklers shall be verified as being clear of excess cement prior to the installation of sprinklers on systems assembled with solvent cement.

    P2904.2.6 Sprinkler modifications prohibited.
    Painting, caulking or modifying of sprinklers shall be prohibited. Sprinklers that have been painted, caulked, modified or damaged shall be replaced with new sprinklers.

    P2904.3 Sprinkler piping system.
    Sprinkler piping shall be supported in accordance with the requirements for cold water distribution piping. Sprinkler piping shall comply with all requirements for cold water distribution piping. For multipurpose piping systems, the sprinkler piping shall connect to and be a part of the cold water distribution piping system.

    P2904.3.1 Nonmetallic pipe and tubing.
    Nonmetallic pipe and tubing, such as CPVC, PEX, and PE-RT shall be listed for use in residential fire sprinkler systems.

    P2904.3.1.1 Nonmetallic pipe protection.
    Nonmetallic pipe and tubing systems shall be protected from exposure to the living space by a layer of not less than 3/8-inch-thick (9.5 mm) gypsum wallboard, 1/2-inch-thick (13 mm) plywood, or other material having a 15-minute fire rating.

    Exceptions:

    1. Pipe protection shall not be required in areas that do not require protection with sprinklers as specified in Section P2904.1.1.

    2. Pipe protection shall not be required where exposed piping is permitted by the pipe listing.

    P2904.3.2 Shutoff valves prohibited.
    With the exception of shutoff valves for the entire water distribution system, valves shall not be installed in any location where the valve would isolate piping serving one or more sprinklers.

    P2904.3.3 Single dwelling limit.
    Piping beyond the service valve located at the beginning of the water distribution system shall not serve more than one dwelling.

    P2904.3.4 Drain.
    A means to drain the sprinkler system shall be provided on the system side of the water distribution shutoff valve.

    P2904.4 Determining system design flow.
    The flow for sizing the sprinkler piping system shall be based on the flow rating of each sprinkler in accordance with Section P2904.4.1 and the calculation in accordance with Section P2904.4.2.

    P2904.4.1 Determining required flow rate for each sprinkler.
    The minimum required flow for each sprinkler shall be determined using the sprinkler manufacturer’s published data for the specific sprinkler model based on all of the following:

    1. The area of coverage.

    2. The ceiling configuration.

    3. The temperature rating.

    4. Any additional conditions specified by the sprinkler manufacturer.

    P2904.4.2 System design flow rate.
    The design flow rate for the system shall be based on the following:

    1. The design flow rate for a room having only one sprinkler shall be the flow rate required for that sprinkler, as determined by Section P2904.4.1.

    2. The design flow rate for a room having two or more sprinklers a shall be determined by identifying the sprinkler in that room with the highest required flow rate, based on Section P2904.4.1, and multiplying that flow rate by 2.

    3. Where the sprinkler manufacturer specifies different criteria for ceiling configurations that are not smooth, flat and horizontal, the required flow rate for that room shall comply with the sprinkler manufacturer’s instructions.

    4. The design flow rate for the sprinkler system shall be the flow required by the room with the largest flow rate, based on Items 1, 2 and 3.

    5. For the purpose of this section, it shall be permissible to reduce the design flow rate for a room by subdividing the space into two or more rooms, where each room is evaluated separately with respect to the required design flow rate. Each room shall be bounded by walls and a ceiling. Openings in walls shall have a lintel not less than 8 inches (203 mm) in depth and each lintel shall form a solid barrier between the ceiling and the top of the opening.

    P2904.5 Water supply.
    The water supply shall provide not less than the required design flow rate for sprinklers in accordance with Section P2904.4.2 at a pressure not less than that used to comply with Section P2904.6.

    P2904.5.1 Water supply from individual sources.
    Where a dwelling unit water supply is from a tank system, a private well system or a combination of these, the available water supply shall be based on the minimum pressure control setting for the pump.

    P2904.5.2 Required capacity.
    The water supply shall have the capacity to provide the required design flow rate for sprinklers for a period of time as follows:

    1. Seven minutes for dwelling units one story in height and less than 2,000 square feet (186 m2) in area.

    2. Ten minutes for dwelling units two or more stories in height or equal to or greater than 2,000 square feet (186 m2) in area.

    Where a well system, a water supply tank system or a combination thereof is used, any combination of well capacity and tank storage shall be permitted to meet the capacity requirement.

    P2904.6 Pipe sizing.
    The piping to sprinklers shall be sized for the flow required by Section P2904.4.2. The flow required to supply the plumbing fixtures shall not be required to be added to the sprinkler design flow.

    P2904.6.1 Method of sizing pipe.
    Piping supplying sprinklers shall be sized using the prescriptive method in Section P2904.6.2 or by hydraulic calculation in accordance with NFPA 13D. The minimum pipe size from the water supply source to any sprinkler shall be 3/4 inch (19 mm) nominal. Threaded adapter fittings at the point where sprinklers are attached to the piping shall be a minimum of 1/2 inch (13 mm) nominal.

    P2904.6.2 Prescriptive pipe sizing method.
    Pipe shall be sized by determining the available pressure to offset friction loss in piping and identifying a piping material, diameter and length using the equation in Section P2904.6.2.1 and the procedure in Section P2904.6.2.2.

    TABLE P2904.6.2(1)
    WATER SERVICE PRESSURE LOSS (PLsvc)a, b

    FLOW RATEc
    (gpm)
    3/4-INCH WATER SERVICE PRESSURE LOSS
    (psi)
    1-INCH WATER SERVICE PRESSURE LOSS
    (psi)
    11/4 -INCH WATER SERVICE PRESSURE
    LOSS (psi)
    Length of water service pipe (feet)Length of water service pipe (feet)Length of water service pipe (feet)
    40 or less41 to 7576 to 100101 to 15040 or less41 to 7576 to 100101 to 15040 or less41 to 7576 to 100101 to 150
    85.18.711.817.41.52.53.45.10.61.01.31.9
    107.713.117.826.32.33.85.27.70.81.42.02.9
    1210.818.424.9NP3.25.47.310.71.22.02.74.0
    1414.424.5NPNP4.27.19.614.31.62.73.65.4
    1618.4NPNPNP5.49.112.418.32.03.44.76.9
    1822.9NPNPNP6.711.415.422.72.54.35.88.6
    2027.8NPNPNP8.113.818.727.63.15.27.010.4
    22NPNPNPNP9.716.522.3NP3.76.28.412.4
    24NPNPNPNP11.419.326.2NP4.37.39.914.6
    26NPNPNPNP13.222.4NPNP5.08.511.416.9
    28NPNPNPNP15.125.7NPNP5.79.713.119.4
    30NPNPNPNP17.2NPNPNP6.511.014.922.0
    32NPNPNPNP19.4NPNPNP7.312.416.824.8
    34NPNPNPNP21.7NPNPNP8.213.918.8NP
    36NPNPNPNP24.1NPNPNP9.115.420.9NP
    For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 0.063 L/s, 1 pound per square inch = 6.895 kPa.
    NP = Not permitted. Pressure loss exceeds reasonable limits.
    a. Values are applicable for underground piping materials listed in Table P2905.4 and are based on an SDR of 11 and a Hazen Williams C Factor of 150.
    b. Values include the following length allowances for fittings: 25% length increase for actual lengths up to 100 feet and 15% length increase for actual lengths over 100 feet.
    c. Flow rate from Section P2904.4.2. Add 5 gpm to the flow rate required by Section P2904.4.2 where the water-service pipe supplies more than one dwelling.

    TABLE P2904.6.2(2)
    MINIMUM WATER METER PRESSURE LOSS (PLm)a

    FLOW RATE
    (gallons per minute, gpm)b
    5/8-INCH METER PRESSURE LOSS
    (pounds per square inch, psi)
    3/4-INCH METER PRESSURE LESS
    (pounds per square inch, psi)
    1-INCH METER PRESSURE LOSS
    (pounds per square inch, psi)
    8211
    10311
    12411
    14521
    16731
    18941
    201142
    22NP52
    24NP52
    26NP62
    28NP62
    30NP72
    32NP73
    34NP83
    36NP83
    For SI: 1 inch = 25.4 mm, 1 pound per square inch = 6.895 kPa, 1 gallon per minute = 0.063 L/s.
    NPNot permitted unless the actual water meter pressure loss is known.
    a. Table P2904.6.2(2) establishes conservative values for water meter pressure loss or installations where the water meter loss is unknown. Where the actual water meter pressure loss is known, Pm shall be the actual loss.
    b. Flow rate from Section P2904.4.2. Add 5 gpm to the flow rate required by Section P2904.4.2 where the water-service pipe supplies more than one dwelling.

    TABLE P2904.6.2(3)
    ELEVATION LOSS (PLe)

    ELEVATION (feet)PRESSURE LOSS (psi)
    52.2
    104.4
    156.5
    208.7
    2510.9
    3013
    3515.2
    4017.4
    For SI: 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa.

    TABLE P2904.6.2(4)
    ALLOWABLE PIPE LENGTH FOR 3/4-INCH TYPE M COPPER WATER TUBING

    SPRINKLER
    FLOW RATEa
    (gpm)
    WATER
    DISTRIBUTION
    SIZE (inch)
    AVAILABLE PRESSURE—Pt (psi)
    15202530354045505560
    Allowable length of pipe from service valve to farthest sprinkler (feet)
    83/4217289361434506578650723795867
    93/4174232291349407465523581639697
    103/4143191239287335383430478526574
    113/4120160200241281321361401441481
    123/4102137171205239273307341375410
    133/488118147177206235265294324353
    143/477103128154180205231257282308
    153/46890113136158181203226248271
    163/46080100120140160180200220241
    173/4547290108125143161179197215
    183/448648197113129145161177193
    193/444587388102117131146160175
    203/44053668093106119133146159
    213/4364861738597109121133145
    223/4334456677889100111122133
    233/431415161728292102113123
    243/42838475766768595104114
    253/4263544536170798897105
    263/424334149576573829098
    273/423303846536169768491
    283/421283643505764717885
    293/420273340475360677380
    303/419253138445056636975
    313/418242935414753596571
    323/417222833394450566167
    333/416212632374247535863
    343/4NP202530354045505560
    353/4NP192428333842475257
    363/4NP182227313640454954
    373/4NP172126303438434751
    383/4NP162024283236404549
    393/4NP151923273135394246
    403/4NPNP1822262933374044
    For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1 gallon per minute = 0.963 L/s.
    NP—Not permitted
    a. Flow rate from Section P2904.4.2.

    TABLE P2904.6.2(5)
    ALLOWABLE PIPE LENGTH FOR 1-INCH TYPE M COPPER WATER TUBING

    SPRINKLER
    FLOW RATEa
    (gpm)
    WATER DISTRIBUTION SIZE (inch)AVAILABLE PRESSURE—Pt (psi)
    15202530354045505560
    Allowable length of pipe from service valve to farthest sprinkler (feet)
    81806107513431612188121492418268729553224
    9164886410801296151217281945216123772593
    1015337118891067124514221600177819562134
    111447586745894104311921341149116401789
    12138150863476188810151142126913961523
    131328438547657766875985109412041313
    14128638247757266876385995410491145
    1512523364205045886727568409241008
    161224298373447522596671745820894
    171200266333400466533600666733799
    181180240300360420479539599659719
    191163217271325380434488542597651
    201148197247296345395444493543592
    211135180225270315360406451496541
    221124165207248289331372413455496
    231114152190228267305343381419457
    241106141176211246282317352387422
    25198131163196228261294326359392
    26191121152182212243273304334364
    27185113142170198226255283311340
    28179106132159185212238265291318
    2917499124149174198223248273298
    3017093116140163186210233256280
    3116688110132153175197219241263
    3216283103124145165186207227248
    331597898117137156176195215234
    341557492111129148166185203222
    351537088105123140158175193210
    361506683100116133150166183199
    37147637995111126142158174190
    38145607590105120135150165181
    39143577286100115129143158172
    4014155688296109123137150164
    For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1 gallon per minute = 0.963 L/s.
    a. Flow rate from Section P2904.4.2.

    TABLE P2904.6.2(6)
    ALLOWABLE PIPE LENGTH FOR 3/4-INCH CPVC PIPE

    SPRINKLER
    FLOW RATEa
    (gpm)
    WATER
    DISTRIBUTION
    SIZE (inch)
    AVAILABLE PRESSURE—Pt (psi)
    15202530354045505560
    Allowable length of pipe from service valve to farthest sprinkler (feet)
    83/43484655816978139291045116112781394
    93/428037446756065474784193410271121
    103/4231307384461538615692769845922
    113/4193258322387451515580644709773
    123/4165219274329384439494549603658
    133/4142189237284331378426473520568
    143/4124165206247289330371412454495
    153/4109145182218254290327363399436
    163/497129161193226258290322354387
    173/486115144173202230259288317346
    183/478104130155181207233259285311
    193/47094117141164188211234258281
    203/46485107128149171192213235256
    213/4587897117136156175195214234
    223/4547189107125143161179197214
    233/449668299115132148165181198
    243/446617691107122137152167183
    253/44256718599113127141155169
    263/43952667992105118131144157
    273/4374961738698110122135147
    283/4344657698092103114126137
    293/432435464758696107118129
    303/430405060708191101111121
    313/42838475766768595104114
    323/4273645546371808998107
    333/4253442515968768493101
    343/424324048566472808896
    353/423303845536168768391
    363/422293643505765727986
    373/420273441485561687582
    383/420263339465259657278
    393/419253137435056626874
    403/418243035414753596571
    For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1 gallon per minute = 0.963 L/s.
    a. Flow rate from Section P2904.4.2.

    TABLE P2904.6.2(7)
    ALLOWABLE PIPE LENGTH FOR 1-INCH CPVC PIPE

    SPRINKLER
    FLOW RATEa
    (gpm)
    WATER
    DISTRIBUTION
    SIZE (inch)
    AVAILABLE PRESSURE—Pt(psi)
    15202530354045505560
    Allowable length of pipe from service valve to farthest sprinkler (feet)
    811049139817482098244727973146349638454195
    91843112514061687196822492530281130933374
    10169492511571388161918512082231425452776
    1115827769701164135815521746194021332327
    121495660826991115613211486165118161981
    13142757071285499711391281142415661709
    1413724976217458699931117124113661490
    151328437546656765874983109312021311
    16129138848558267977687397010671164
    1712603474335206076937808679541040
    181234312390468546624702780858936
    191212282353423494565635706776847
    201193257321385449513578642706770
    211176235293352410469528586645704
    221161215269323377430484538592646
    231149198248297347396446496545595
    241137183229275321366412458504550
    251127170212255297340382425467510
    261118158197237276316355395434474
    271111147184221258295332368405442
    281103138172207241275310344379413
    29197129161194226258290323355387
    30191121152182212242273303333364
    31186114143171200228257285314342
    32181108134161188215242269296323
    33176102127152178203229254280305
    3417296120144168192216240265289
    3516891114137160182205228251273
    3616587108130151173195216238260
    3716282103123144165185206226247
    381597898117137157176196215235
    391567593112131149168187205224
    401537189107125142160178196214
    For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1 gallon per minute = 0.963 L/s.
    a. Flow rate from Section P2904.4.2.

    TABLE P2904.6.2(8)
    ALLOWABLE PIPE LENGTH FOR 3/4-INCH PEX AND PE-RT TUBING

    SPRINKLER
    FLOW RATEa
    (gpm)
    WATER
    DISTRIBUTION
    SIZE (inch)
    AVAILABLE PRESSURE—Pt (psi)
    15202530354045505560
    Allowable length of pipe from service valve to farthest sprinkler (feet)
    83/493123154185216247278309339370
    93/47499124149174199223248273298
    103/46182102123143163184204225245
    113/4516886103120137154171188205
    123/444587387102117131146160175
    133/43850637588101113126138151
    143/433445566778899110121132
    153/42939485868778796106116
    163/4263443516068778694103
    173/423313846546169778492
    183/421283441485562697683
    193/419253137445056626975
    203/417232834404551576268
    213/416212631364147525762
    223/4NP192428333843475257
    233/4NP172226313539444852
    243/4NP162024283236404449
    253/4NPNP1922263034374145
    263/4NPNP1721242831353842
    273/4NPNP1620232629333639
    283/4NPNP1518212427303336
    293/4NPNPNP17202326283134
    303/4NPNPNP16192124272932
    313/4NPNPNP15182023252830
    323/4NPNPNPNP171921242628
    333/4NPNPNPNP161820222527
    343/4NPNPNPNPNP1719212325
    353/4NPNPNPNPNP1618202224
    363/4NPNPNPNPNP1517192123
    373/4NPNPNPNPNPNP16182022
    383/4NPNPNPNPNPNP16171921
    393/4NPNPNPNPNPNPNP161820
    403/4NPNPNPNPNPNPNP161719
    For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1 gallon per minute = 0.963 L/s.
    NP— Not permitted.
    a. Flow rate from Section P2904.4.2.

    TABLE P2904.6.2(9)
    ALLOWABLE PIPE LENGTH FOR 1-INCH PEX AND PE-RT TUBING

    SPRINKLER
    FLOW RATEa
    (gpm)
    WATER
    DISTRIBUTION
    SIZE (inch)
    AVAILABLE PRESSURE—Pt (psi)
    15202530354045505560
    Allowable length of pipe from service valve to farthest sprinkler (feet)
    81314418523628732837941104611511255
    912523364215055896737578419251009
    101208277346415485554623692761831
    111174232290348406464522580638696
    121148198247296346395445494543593
    131128170213256298341383426469511
    141111149186223260297334371409446
    15198131163196229262294327360392
    16187116145174203232261290319348
    17178104130156182208233259285311
    1817093117140163187210233257280
    1916384106127148169190211232253
    201587796115134154173192211230
    211537088105123140158175193211
    22148648097113129145161177193
    23144597489104119133148163178
    2414155698296110123137151164
    2513851647689102114127140152
    261354759718395106118130142
    27133445566778899110121132
    28131415262728293103113124
    2912939485868778797106116
    3012736455463738291100109
    311263443516068778594102
    32124324048566472808997
    33123303846536168768491
    34122293643505865727986
    35120273441485561687582
    36119263239455258657178
    37118253137434955626874
    38118232935414753596470
    39117222833394550566167
    40116212732374348535964
    For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square inch = 6.895 kPa, 1 gallon per minute = 0.963 L/s.
    a. Flow rate from Section P2904.4.2.

    P2904.6.2.1 Available pressure equation.
    The pressure available to offset friction loss in the interior piping system (Pt) shall be determined in accordance with the Equation 29-1.

    Pt = Psup - PLsvc - PLm - PLd - PLe - Psp(Equation 29-1)

    where:

    Pt =Pressure used in applying Tables P2904.6.2(4) through P2904.6.2(9).
    Psup=Pressure available from the water supply source.
    PLsvc =Pressure loss in the water-service pipe.
    PLm=Pressure loss in the water meter.
    PLd=Pressure loss from devices other than the water meter.
    PLe=Pressure loss associated with changes in elevation.
    Psp=Maximum pressure required by a sprinkler.

    P2904.6.2.2 Calculation procedure.
    Determination of the required size for water distribution piping shall be in accordance with the following procedure:

    Step 1—Determine Psup

    Obtain the static supply pressure that will be available from the water main from the water purveyor, or for an individual source, the available supply pressure shall be in accordance with Section P2904.5.1.

    Step 2—Determine PLsvc

    Use Table P2904.6.2(1) to determine the pressure loss in the water service pipe based on the selected size of the water service.

    Step 3—Determine PLm

    Use Table P2904.6.2(2) to determine the pressure loss from the water meter, based on the selected water meter size.

    Step 4—Determine PLd

    Determine the pressure loss from devices other than the water meter installed in the piping system supplying sprinklers, such as pressure-reducing valves, backflow preventers, water softeners or water filters. Device pressure losses shall be based on the device manufacturer’s specifications. The flow rate used to determine pressure loss shall be the rate from Section P2904.4.2, except that 5 gpm (0.3 L/s) shall be added where the device is installed in a water-service pipe that supplies more than one dwelling. As alternative to deducting pressure loss for a device, an automatic bypass valve shall be installed to divert flow around the device when a sprinkler activates.

    Step 5—Determine PLe

    Use Table P2904.6.2(3) to determine the pressure loss associated with changes in elevation. The elevation used in applying the table shall be the difference between the elevation where the water source pressure was measured and the elevation of the highest sprinkler.

    Step 6—Determine Psp

    Determine the maximum pressure required by any individual sprinkler based on the flow rate from Section P2904.4.1. The required pressure is provided in the sprinkler manufacturer’s published data for the specific sprinkler model based on the selected flow rate.

    Step 7—Calculate Pt

    Using Equation 29-1, calculate the pressure available to offset friction loss in water-distribution piping between the service valve and the sprinklers.

    Step 8—Determine the maximum allowable pipe length

    Use Tables P2904.6.2(4) through P2904.6.2(9) to select a material and size for water distribution piping. The piping material and size shall be acceptable if the developed length of pipe between the service valve and the most remote sprinkler does not exceed the maximum allowable length specified by the applicable table. Interpolation of Pt between the tabular values shall be permitted.

    The maximum allowable length of piping in Tables P2904.6.2(4) through P2904.6.2(9) incorporates an adjustment for pipe fittings, and no additional consideration of friction losses associated with pipe fittings shall be required.

    P2904.7 Instructions and signs.
    An owner’s manual for the fire sprinkler system shall be provided to the owner. A sign or valve tag shall be installed at the main shutoff valve to the water distribution system stating the following: “Warning, the water system for this home supplies fire sprinklers that require certain flows and pressures to fight a fire. Devices that restrict the flow or decrease the pressure or automatically shut off the water to the fire sprinkler system, such as water softeners, filtration systems and automatic shutoff valves, shall not be added to this system without a review of the fire sprinkler system by a fire protection specialist. Do not remove this sign.”

    P2904.8 Inspections.
    The water distribution system shall be inspected in accordance with Sections P2904.8.1 and P2904.8.2.

    P2904.8.1 Preconcealment inspection.
    The following items shall be verified prior to the concealment of any sprinkler system piping:

    1. Sprinklers are installed in all areas as required by Section P2904.1.1.

    2. Where sprinkler water spray patterns are obstructed by construction features, luminaires or ceiling fans, additional sprinklers are installed as required by Section P2904.2.4.2.

    3. Sprinklers are the correct temperature rating and are installed at or beyond the required separation distances from heat sources as required by Sections P2904.2.1 and P2904.2.2.

    4. The pipe size equals or exceeds the size used in applying Tables P2904.6.2(4) through P2904.6.2(9) or, if the piping system was hydraulically calculated in accordance with Section P2904.6.1, the size used in the hydraulic calculation.

    5. The pipe length does not exceed the length permitted by Tables P2904.6.2(4) through P2904.6.2(9) or, if the piping system was hydraulically calculated in accordance with Section P2904.6.1, pipe lengths and fittings do not exceed those used in the hydraulic calculation.

    6. Nonmetallic piping that conveys water to sprinklers is listed for use with fire sprinklers.

    7. Piping is supported in accordance with the pipe manufacturer’s and sprinkler manufacturer’s installation instructions.

    8. The piping system is tested in accordance with Section P2503.7.

    P2904.8.2 Final inspection.
    The following items shall be verified upon completion of the system:

    1. Sprinkler are not painted, damaged or otherwise hindered from operation.

    2. Where a pump is required to provide water to the system, the pump starts automatically upon system water demand.

    3. Pressure-reducing valves, water softeners, water filters or other impairments to water flow that were not part of the original design have not been installed.

    4. The sign or valve tag required by Section P2904.7 is installed and the owner’s manual for the system is present.

    SECTION P2905
    MATERIALS, JOINTS AND CONNECTIONS

    P2905.1 Soil and groundwater.
    The installation of water service pipe, water distribution pipe, fittings, valves, appurtenances and gaskets shall be prohibited in soil and groundwater that is contaminated with solvents, fuels, organic compounds or other detrimental materials that cause permeation, corrosion, degradation or structural failure of the water service or water distribution piping material.

    P2905.1.1 Investigation required.
    Where detrimental conditions are suspected by or brought to the attention of the building official, a chemical analysis of the soil and groundwater conditions shall be required to ascertain the acceptability of the water service material for the specific installation.

    P2905.1.2 Detrimental condition.
    When a detrimental condition exists, approved alternate materials or alternate routing shall be required.

    P2905.2 Lead content.
    Pipe and fittings used in the water-supply system shall have lead content of not greater than 8 percent lead.

    P2905.3 Polyethylene plastic piping installation.
    Polyethylene pipe shall be cut square using a cutter designed for plastic pipe. Except where joined by heat fusion, pipe ends shall be chamfered to remove sharp edges. Pipe that has been kinked shall not be installed. For bends, the installed radius of pipe curvature shall be greater than 30 pipe diameters or the coil radius when bending with the coil. Coiled pipe shall not be bent beyond straight. Bends shall not be permitted within 10 pipe diameters of any fitting or valve. Joints between polyethylene plastic pipe and fittings shall comply with Sections P2905.3.1 and P2905.3.2.

    P2905.3.1 Heat-fusion joints.
    Joint surfaces shall be clean and free from moisture. Joint surfaces shall be heated to melting temperature and joined. The joint shall be undisturbed until cool. Joints shall be made in accordance with ASTM D 2657.

    P2905.3.2 Mechanical joints.
    Mechanical joints shall be installed in accordance with the manufacturer’s instructions.

    P2905.4 Water service pipe.
    Water service pipe shall conform to NSF 61 and shall conform to one of the standards listed in Table P2905.4. Water service pipe or tubing, installed underground and outside of the structure, shall have a working pressure rating of not less than 160 pounds per square inch at 73°F (1103 kPa at 23°C). Where the water pressure exceeds 160 pounds per square inch (1103 kPa), piping material shall have a rated working pressure equal to or greater than the highest available pressure. Water service piping materials not third-party certified for water distribution shall terminate at or before the full open valve located at the entrance to the structure. Ductile iron water service piping shall be cement mortar lined in accordance with AWWA C104.

    TABLE P2905.4
    WATER SERVICE PIPE

    MATERIALSTANDARD
    Acrylonitrile butadiene styrene (ABS) plastic pipe ASTM D 1527; ASTM D 2282
    Asbestos-cement pipe ASTM C 296
    Brass pipe ASTM B 43
    Chlorinated polyvinyl chloride (CPVC) plastic pipe ASTM D 2846; ASTM F 441; ASTM F 442; CSA B137.6
    Copper or copper-alloy pipe ASTM B 42; ASTM B 302
    Copper or copper-alloy tubing (Type K, WK, L, WL, M or WM) ASTM B 75; ASTM B 88; ASTM B 251; ASTM B 447
    Cross-linked polyethylene/aluminum/cross-linked polyethylene (PEX-AL-PEX) pipe ASTM F 1281; ASTM F 2262; CSA B137.10M
    Cross-linked polyethylene/aluminum/high-density polyethylene (PEX-AL-HDPE) ASTM F 1986
    Cross-linked polyethylene (PEX) plastic tubing ASTM F 876; ASTM F 877; CSA B137.5
    Ductile iron water pipe AWWA C151; AWWA C115
    Galvanized steel pipe ASTM A 53
    Polyethylene/aluminum/polyethylene (PE-AL-PE) pipe ASTM F 1282; CSA B137.9
    Polyethylene (PE) plastic pipe ASTM D 2104; ASTM D 2239; AWWA C901; CSA B137.1
    Polyethylene (PE) plastic tubing ASTM D 2737; AWWA C901; CSA B137.1
    Polyethylene of raised temperature (PE-RT) plastic tubingASTM F 2769
    Polyvinyl chloride (PVC) plastic pipe ASTM D 1785; ASTM D 2241; ASTM D 2672; CSA B137.3
    Stainless steel (Type 304/304L) pipe ASTM A 312; ASTM A 778
    Stainless steel (Type 316/316L) pipe ASTM A 312; ASTM A 778

    P2905.4.1 Dual check-valve-type backflow preventer.
    Where a dual check-valve backflow preventer is installed on the water supply system, it shall comply with ASSE 1024 or CSA B64.6.

    P2905.4.2 Water service installation.
    Trenching, pipe installation and backfilling shall be in accordance with Section P2604. Water-service pipe is permitted to be located in the same trench with a building sewer provided such sewer is constructed of materials listed for underground use within a building in Section P3002.1. If the building sewer is not constructed of materials listed in Section P3002.1, the water-service pipe shall be separated from the building sewer by not less than 5 feet (1524 mm), measured horizontally, of undisturbed or compacted earth or placed on a solid ledge not less than 12 inches (305 mm) above and to one side of the highest point in the sewer line.

    Exception: The required separation distance shall not apply where a water service pipe crosses a sewer pipe, provided that the water service pipe is sleeved not less than 5 feet (1524 mm), horizontally from the sewer pipe centerline, on both sides of the crossing with pipe materials listed in Table P2905.4, P3002.1(1), P3002.1(2) or P3002.2.

    P2905.5 Water-distribution pipe.
    Water-distribution piping within dwelling units shall conform to NSF 61 and shall conform to one of the standards listed in Table P2905.5. All hot-water-distribution pipe and tubing shall have a pressure rating of not less than 100 psi at 180°F (689 kPa at 82°C).

    TABLE P2905.5
    WATER DISTRIBUTION PIPE

    MATERIALSTANDARD
    Brass pipeASTM B 43
    Chlorinated polyvinyl chloride (CPVC) plastic pipe and tubingASTM D 2846; ASTM F 441; ASTM F 442;
    CSA B137.6
    Copper or copper-alloy pipeASTM B 42; ASTM B 302
    Copper or copper-alloy tubing (Type K, WK, L, WL, M or WM)ASTM B 75; ASTM B 88; ASTM B 251;
    ASTM B 447
    Cross-linked polyethylene (PEX) plastic tubingASTM F 876; ASTM F 877; CSA B137.5
    Cross-linked polyethylene/aluminum/cross-linked polyethylene (PEX-AL-PEX) pipeASTM F 1281; ASTM F 2262; CSA B137.10M
    Cross-linked polyethylene/aluminum/high-density polyethylene (PEX-AL-HDPE)ASTM F 1986
    Galvanized steel pipeASTM A 53
    Polyethylene/aluminum/polyethylene (PE-AL-PE) composite pipeASTM F 1282
    Polyethylene of raised temperature (PE-RT) plastic tubingASTM F 2769
    Polypropylene (PP) plastic pipe or tubingASTM F 2389; CSA B137.11
    Stainless steel (Type 304/304L) pipeASTM A 312; ASTM A 778

    P2905.6 Fittings.
    Pipe fittings shall be approved for installation with the piping material installed and shall comply with the applicable standards listed in Table P2905.6. All pipe fittings used in water supply systems shall also comply with NSF 61.

    TABLE P2905.6
    PIPE FITTINGS

    MATERIALSTANDARD
    Acrylonitrile butadiene styrene (ABS) plasticASTM D 2468
    BrassASTM F1974
    Cast-ironASME B16.4; ASME B16.12
    Chlorinated polyvinyl chloride (CPVC) plasticASSE 1061; ASTM D 2846; ASTM F 437; ASTM F 438;
    ASTM F 439; CSA B137.6
    Copper or copper alloyASSE 1061; ASME B16.15; ASME B16.18; ASME B16.22;
    ASME B16.23; ASME B16.26; ASME B16.29
    Cross-linked polyethylene/aluminum/high-density polyethylene (PEX-AL-HDPE)ASTM F 1986
    Fittings for cross-linked polyethylene (PEX) plastic tubingASSE 1061; ASTM F 877; ASTM F 1807; ASTM F 1960;
    ASTM F 2080; ASTM F 2098; ASTM F 2159; ASTM F 2434; ASTM F 2735; CSA B137.5
    Gray iron and ductile ironAWWA C110; AWWA C153
    Malleable ironASME B16.3
    Insert fittings for
    Polyethylene/aluminum/polyethylene (PE-AL-PE) and cross-linked polyethylene/aluminum/polyethylene (PEX-AL-PEX)
    ASTM F 1974; ASTM F 1281; ASTM F 1282; CSA B137.9;
    CSA B137.10
    Polyethylene (PE) plasticASTM D 2609; CSA B137.1
    Fittings for polyethylene of raised temperature (PE-RT) plastic tubingASTM F 1807; ASTM F2098; ASTM F 2159; ASTM F 2735
    Polypropylene (PP) plastic pipe or tubingASTM F 2389; CSA B137.11
    Polyvinyl chloride (PVC) plasticASTM D 2464; ASTM D 2466; ASTM D 2467; CSA B137.2;
    CSA B137.3
    Stainless steel (Type 304/304L) pipeASTM A 312; ASTM A 778
    Stainless steel (Type 316/316L) pipeASTM A 312; ASTM A 778
    SteelASME B16.9; ASME B16.11; ASME B16.28

    P2905.7 Flexible water connectors.
    Flexible water connectors, exposed to continuous pressure, shall conform to ASME A112.18.6/CSA B125.6. Access shall be provided to all flexible water connectors.

    P2905.8 Joint and connection tightness.
    Joints and connections in the plumbing system shall be gas tight and water tight for the intended use or required test pressure.

    P2905.9 Plastic pipe joints.
    Joints in plastic piping shall be made with approved fittings by solvent cementing, heat fusion, corrosion-resistant metal clamps with insert fittings or compression connections. Flared joints for polyethylene pipe shall be permitted in accordance with Section P2905.3.

    P2905.9.1 Solvent cementing.
    Solvent-cemented joints shall comply with Sections P2905.9.1.1 through P2905.9.1.3.

    P2905.9.1.1 ABS plastic pipe.
    Solvent cement for ABS plastic pipe conforming to ASTM D 2235 shall be applied to all joint surfaces.

    P2905.9.1.2 CPVC plastic pipe.
    Joint surfaces shall be clean and free from moisture and an approved primer shall be applied. Solvent cement for CPVC plastic pipe, orange in color and conforming to ASTM F 493, shall be applied to all joint surfaces. The parts shall be joined while the cement is wet and in accordance with ASTM D 2846 or ASTM F 493. Solvent-cement joints shall be permitted above or below ground.

    Exception: A primer shall not be required where all of the following conditions apply:

    1. The solvent cement used is third-party certified as conforming to ASTM F 493.

    2. The solvent cement used is yellow in color.

    3. The solvent cement is used only for joining 1/2 inch (13 mm) through 2 inch (51 mm) diameter CPVC pipe and fittings.

    4. The CPVC pipe and fittings are manufactured in accordance with ASTM D 2846.

    P2905.9.1.3 PVC plastic pipe.
    A purple primer that conforms to ASTM F 656 shall be applied to PVC solvent-cemented joints. Solvent cement for PVC plastic pipe conforming to ASTM D 2564 shall be applied to all joint surfaces.

    P2905.9.1.4 Cross-linked polyethylene plastic (PEX).
    Joints between cross-linked polyethylene plastic tubing or fittings shall comply with Section P2905.9.1.4.1 or Section P2905.9.1.4.

    P2905.9.1.4.1 Flared joints.
    Flared pipe ends shall be made by a tool designed for that operation.

    P2905.9.1.4.2 Mechanical joints.
    Mechanical joints shall be installed in accordance with the manufacturer’s instructions. Fittings for cross-linked polyethylene (PEX) plastic tubing shall comply with the applicable standards listed in Table P2905.6 and shall be installed in accordance with the manufacturer’s instructions. PEX tubing shall be factory marked with the applicable standards for the fittings that the PEX manufacturer specifies for use with the tubing.

    P2905.10 Polypropylene (PP) plastic.
    Joints between polypropylene plastic pipe and fittings shall comply with Section P2905.10.1 or P2905.10.2.

    P2905.10.1 Heat-fusion joints.
    Heat fusion joints for polypropylene pipe and tubing joints shall be installed with socket-type heat-fused polypropylene fittings, butt-fusion polypropylene fittings or electrofusion polypropylene fittings. Joint surfaces shall be clean and free from moisture. The joint shall be undisturbed until cool. Joints shall be made in accordance with ASTM F 2389.

    P2905.10.2 Mechanical and compression sleeve joints.
    Mechanical and compression sleeve joints shall be installed in accordance with the manufacturer’s instructions.

    P2905.11 Cross-linked polyethylene/aluminum/cross-linked polyethylene.
    Joints between polyethylene/aluminum/polyethylene (PE-AL-PE) and cross-linked polyethylene/aluminum/cross-linked polyethylene (PEX-AL-PEX) pipe and fittings shall comply with Section P2905.11.1.

    P2905.11.1 Mechanical joints.
    Mechanical joints shall be installed in accordance with the manufacturer’s instructions. Fittings for PE-AL-PE and PEX-AL-PEX as described in ASTM F 1974, ASTM F 1281, ASTM F 1282, CSA B137.9 and CSA B137.10 shall be installed in accordance with the manufacturer’s instructions.

    P2905.12 Stainless steel.
    Joints between stainless steel pipe and fittings shall comply with Sections P2905.12.1 and P2905.12.2.

    P2905.12.1 Mechanical joints.
    Mechanical joints shall be installed in accordance with the manufacturer’s instructions.

    P2905.12.2 Welded joints.
    Joint surfaces shall be cleaned. The joint shall be welded autogenously or with an approved filler metal in accordance with ASTM A 312.

    P2905.13 Threaded pipe joints.
    Threaded joints shall conform to American National Taper Pipe Thread specifications. Pipe ends shall be deburred and chips removed. Pipe joint compound shall be used only on male threads.

    P2905.14 Soldered joints.
    Soldered joints in tubing shall be made with fittings approved for water piping and shall conform to ASTM B 828. Surfaces to be soldered shall be cleaned bright. The joints shall be properly fluxed and made with approved solder. Solders and fluxes used in potable water-supply systems shall have a lead content of not greater than 0.2 percent. Fluxes shall conform to ASTM B 813.

    P2905.15 Flared joints.
    Flared joints in water tubing shall be made with approved fittings. The tubing shall be reamed and then expanded with a flaring tool.

    P2905.16 Above-ground joints.
    Joints within the building between copper pipe or CPVC tubing, in any combination with compatible outside diameters, shall be permitted to be made with the use of approved push-in mechanical fittings of a pressure-lock design.

    P2905.17 Joints between different materials.
    Joints between different piping materials shall be made in accordance with Sections P2905.17.1, P2905.17.2 and P2905.17.3 or with a mechanical joint of the compression or mechanical sealing type having an elastomeric seal conforming to ASTM D 1869 or ASTM F 477. Joints shall be installed in accordance with the manufacturer’s instructions.

    P2905.17.1 Copper or copper-alloy tubing to galvanized steel pipe.
    Joints between copper or copper-alloy tubing and galvanized steel pipe shall be made with a brass fitting or dielectric fitting. The copper tubing shall be joined to the fitting in an approved manner, and the fitting shall be screwed to the threaded pipe.

    P2904.17.2 Plastic pipe or tubing to other piping material.
    Joints between different types of plastic pipe or between plastic pipe and other piping material shall be made with an approved adapter fitting.

    P2905.17.3 Stainless steel.
    Joints between stainless steel and different piping materials shall be made with a mechanical joint of the compression or mechanical-sealing type or a dielectric fitting.

    P2905.18 Press joints.
    Press-type mechanical joints in copper tubing shall be made in accordance with the manufacturer’s instructions using approved tools which affix the copper fitting with integral O-ring to the tubing.

    P2905.19 Polyethylene of raised temperature plastic.
    Joints between polyethylene of raised temperature plastic tubing and fittings shall be in accordance with Section P2905.19.1 and Section P2905.19.2

    P2905.19.1 Flared joints.
    Flared pipe ends shall be made by a tool designed for that operation.

    P2905.19.2 Mechanical joints.
    Mechanical joints shall be installed in accordance with the manufacturer’s instructions. Fittings for polyethylene of raised temperature plastic tubing shall comply with the applicable standards listed in Table P2905.6 and shall be installed in accordance with the manufacturer’s instructions. Polyethylene of raised temperature plastic tubing shall be factory marked with the applicable standards for the fittings that the manufacturer of the tubing specifies for use with the tubing.

    SECTION P2906
    CHANGES IN DIRECTION

    P2906.1 Bends.
    Changes in direction in copper tubing are permitted to be made with bends having a radius of not less than four diameters of the tube, providing such bends are made by use of forming equipment that does not deform or create loss in cross-sectional area of the tube.

    SECTION P2907
    SUPPORT

    P2907.1 General.
    Pipe and tubing support shall conform to Section P2605.

    SECTION P2908
    DRINKING WATER TREATMENT UNITS

    P2908.1 Design.
    Drinking water treatment units shall meet the requirements of NSF42, NSF 44, NSF 53, NSF 60 or CSA B483.1.

    P2908.2 Reverse osmosis drinking water treatment units.
    Point-of-use reverse osmosis drinking water treatment units, designed for residential use, shall meet the requirements of NSF 58 or CSA B483.1. Waste or discharge from reverse osmosis drinking water treatment units shall enter the drainage system through an air gap or an air gap device that meets the requirements of NSF 58.

    P2908.3 Connection tubing.
    The tubing to and from drinking water treatment units shall be of a size and material as recommended by the manufacturer. The tubing shall comply with NSF 14, NSF 42, NSF 44, NSF 53, NSF 58 or NSF 61.