CODES

ADOPTS WITH AMENDMENTS:

International Residential Code 2009 (IRC 2009)

Heads up: There are no suggested sections in this chapter.
Heads up: There are no amended sections in this chapter.
Dwelling units shall be supplied with potable water in the amounts and pressures specified in this chapter. In a building 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, rain water and gray water distribution systems. Any nonpotable outlet that could inadvertently be used for drinking or domestic purposes shall be posted.
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 unless an approved backflow-prevention device is provided. Cross-connections between an individual water supply and a potable public water supply shall be prohibited.
The supply lines and fittings for every plumbing fixture shall be installed to prevent backflow. Plumbing fixture fittings shall provide backflow protection in accordance with ASME A112.18.1.

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

DEVICE

DEGREE OF HAZARDa

APPLICATIONb

APPLICABLE
STANDARDS

Air gap

High or low hazard

Backsiphonage or backpressure

ASME A112.1.2

Air gap fittings for use with plumbing fixtures, appliances and appurtenances

High or low hazard

Backsiphonage or backpressure

ASME A112.1.3

Antisiphon-type fill valves for gravity water closet flush tanks

High hazard

Backsiphonage only

ASSE 1002,
CSA B125.3

Backflow preventer with intermediate atmospheric vents

Low hazard

Backpressure 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 hazard

Backpressure 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 hazard

Backpressure or backsiphonage

(Fire sprinkler systems)
Sizes 2" — 16"

ASSE 1048

Dual-check-valve-type backflow preventer

Low hazard

Backpressure or backsiphonage

Sizes 1/4" — 1"

ASSE 1024, CSA B64.6

Hose connection backflow preventer

High or low hazard

Low 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 hazard

Low head backpressure or backsiphonage

Sizes 1/2", 3/4", 1"

ASSE 1011,
CSA B64.2, CSA B64.2.1

Laboratory faucet backflow preventer

High or low hazard

Low head backpressure and backsiphonage

ASSE 1035, CSA B64.7

Pipe-applied atmospheric-type vacuum breaker

High or low hazard

Backsiphonage only

Sizes 1/4" — 4"

ASSE 1001, CSA B64.1.1

Pressure vacuum breaker assembly

High or low hazard

Backsiphonage only

Sizes 1/2" — 2"

ASSE 1020, CSA B64.1.2

Reduced pressure detector fire protection backflow prevention assemblies

High or low hazard

Backsiphonage or backpressure
(Fire sprinkler systems)

ASSE 1047

Reduced pressure principle backflow preventer and reduced pressure principle fire protection backflow preventer

High or low hazard

Backpressure or backsiphonage
Sizes 3/8" — 16"

ASSE 1013,
AWWA C511,
CSA B64.4, CSA B64.4.1

Spillproof vacuum breaker

High or low hazard

Backsiphonage only
Sizes 1/4" — 2"

ASSE 1056

Vacuum breaker wall hydrants, frost-resistant, automatic draining type

High or low hazard

Low head backpressure or backsiphonage
Sizes 3/4" — 1"

ASSE 1019, CSA B64.2.2

For SI: 1 inch = 25.4 mm.

  1. Low hazard—See Pollution (Section 202). High hazard—See Contamination (Section 202).
  2. See Backpressure (Section 202). See Backpressure, Low Head (Section 202). See Backsiphonage (Section 202).

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

FIXTURE

MINIMUM 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

1

1.5

Over-rim bath fillers and other fixtures with effective openings not greater than 1 inch in diameter

2

3

Sink, laundry trays, gooseneck back faucets and other fixtures with effective openings not greater than 3/4 inch in diameter

1.5

2.5

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.

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.
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.
Pressure- type vacuum breakers shall conform to ASSE 1020 or CSA B64.1.2 and spillproof vacuum breakers shall comply with ASSE 1056. These devices are designed for installation under continuous pressure conditions when the critical level is installed at the required height. Pressure-type vacuum breakers shall not be installed in locations where spillage could cause damage to the structure.
Reduced pressure principle backflow preventers shall conform to ASSE 1013, AWWA C511, CSA B64.4 or CSA B64.4.1. Reduced pressure detector assembly backflow preventers 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.
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.
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.
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 at least 1 inch (25 mm) above the full opening of the overflow pipe.
Approved deck-mounted vacuum breakers and faucets with integral atmospheric or spill-proof vacuum breakers shall be installed in accordance with the manufacturer's installation instructions and the requirements for labeling with the critical level not less than 1 inch (25 mm) above the flood level rim.

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.
Connections to the potable water shall conform to Sections P2902.5.1 through P2902.5.5.
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.
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.
The potable water supply to lawn irrigation systems shall be protected against backflow by an atmospheric-type vacuum breaker, a pressure-type vacuum breaker or a reduced pressure principle backflow preventer. A valve 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 preventer.

The potable water supply to automatic fire sprinkler systems shall be protected against backflow by a double check-valve assembly or a reduced pressure principle backflow preventer.

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, isolation of the water supply system shall not be required.

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 preventer. Where chemical additives or antifreeze is added to only a portion of an automatic fire sprinkler or standpipe system, the reduced pressure principle backflow preventer shall be permitted to be located so as to isolate that portion of the system.

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

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 OUTLET

FLOW RATE (gpm)

FLOW PRESSURE
(psi)

Bathtub, pressure-balanced or thermostatic mixing valve

4

20

Bidet, thermostatic mixing

2

20

Dishwasher

2.75

8

Laundry tub

4

8

Lavatory

2

8

Shower, pressure-balancing or thermostatic mixing valve

3

20

Sillcock, hose bibb

5

8

Sink

2.5

8

Water closet, flushometer tank

1.6

20

Water closet, tank, close coupled

3

20

Water closet, tank, one-piece

6

20

For SI: 1 gallon per minute = 3.785 L/m,
1 pound per square inch = 6.895 kPa.

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 faucet

2.2 gpm at 60 psi

Shower heada

2.5 gpm at 80 psi

Sink faucet

2.2 gpm at 60 psi

Water closet

1.6 gallons per flushing cycle

For SI: 1 gallon per minute = 3.785 L/m,
1 pound per square inch = 6.895 kPa.

  1. A handheld shower spray is also a shower head.
  2. Consumption tolerances shall be determined from referenced standards.
Minimum static pressure (as determined by the local water authority) at the building entrance for either public or private water service shall be 40 psi (276 kPa).
Maximum static pressure shall be 80 psi (551 kPa). When main pressure exceeds 80 psi (551 kPa), an approved pressure-reducing valve conforming to ASSE 1003 shall be installed on the domestic water branch main or riser at the connection to the water-service pipe.
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.
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.
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.
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.

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 FIXTURES

WATER-SUPPLY FIXTURE-UNIT VALUE (w.s.f.u.)

Hot

Cold

Combined

Bathtub (with/without overhead shower head)

1.0

1.0

1.4

Clothes washer

1.0

1.0

1.4

Dishwasher

1.4

1.4

Full-bath group with bathtub (with/without shower head) or shower stall

1.5

2.7

3.6

Half-bath group (water closet and lavatory)

0.5

2.5

2.6

Hose bibb (sillcock)a

2.5

2.5

Kitchen group (dishwasher and sink with/without garbage grinder)

1.9

1.0

2.5

Kitchen sink

1.0

1.0

1.4

Laundry group (clothes washer standpipe and laundry tub)

1.8

1.8

2.5

Laundry tub

1.0

1.0

1.4

Lavatory

0.5

0.5

0.7

Shower stall

1.0

1.0

1.4

Water closet (tank type)

2.2

2.2

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 TANKS

SUPPLY SYSTEM PREDOMINANTLY FOR FLUSH VALVES

Load

Demand

Load

Demand

(Water supply
fixture units)

(Gallons per minute)

(Cubic feet per minute)

(Water supply
fixture units)

(Gallons per minute)

(Cubic feet per minute)

1

3.0

0.04104

2

5.0

0.0684

3

6.5

0.86892

4

8.0

1.06944

5

9.4

1.256592

5

15.0

2.0052

6

10.7

1.430376

6

17.4

2.326032

7

11.8

1.577424

7

19.8

2.646364

8

12.8

1.711104

8

22.2

2.967696

9

13.7

1.831416

9

24.6

3.288528

10

14.6

1.951728

10

27.0

3.60936

11

15.4

2.058672

11

27.8

3.716304

12

16.0

2.13888

12

28.6

3.823248

13

16.5

2.20572

13

29.4

3.930192

14

17.0

2.27256

14

30.2

4.037136

15

17.5

2.3394

15

31.0

4.14408

16

18.0

2.90624

16

31.8

4.241024

17

18.4

2.459712

17

32.6

4.357968

18

18.8

2.513184

18

33.4

4.464912

19

19.2

2.566656

19

34.2

4.571856

20

19.6

2.620128

20

35.0

4.6788

25

21.5

2.87412

25

38.0

5.07984

30

23.3

3.114744

30

42.0

5.61356

35

24.9

3.328632

35

44.0

5.88192

40

26.3

3.515784

40

46.0

6.14928

45

27.7

3.702936

45

48.0

6.41664

50

29.1

3.890088

50

50.0

6.684

For SI: 1 gallon per minute = 3.785 L/m, 1 cubic foot per minute = 0.4719 L/s.

The minimum size water service pipe shall be 3/4 inch (19 mm). 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.
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.

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

PLASTIC

METALLIC

Nominal Size ID
(inches)

Maximuma
gpm

Nominal Size ID
(inches)

Maximuma
gpm

3/4

17

3/4

11

1

29

1

20

11/4

46

11/4

31

11/2

66

11/2

44

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 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.

Where the developed length of the distribution line is 60 feet (18 288 mm) or less, and the available pressure at the meter is a minimum of 40 pounds per square inch (276 kPa), the minimum size of individual distribution lines shall be 3/8 inch (10 mm). 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.
Manifolds shall be permitted to be installed in a horizontal or vertical position.
Plastic piping bundles shall be secured in accordance with the manufacturer's installation 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.
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.
A readily accessible air bleed shall be installed in hose bibb supplies at the manifold or at the hose bibb exit point.
Valves shall be installed in accordance with Sections P2903.9.1 through P2903.9.5.
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 property line in accordance with local requirements.
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.
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.
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.

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."

Hose bibbs subject to freezing, including the "frost-proof" type, shall be equipped with an accessible stop-and-waste-type valve inside the building so that they can be controlled and/or 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

Where installed, residential fire sprinkler systems, or portions thereof, shall be in accordance with NFPA 13D or Section P2904, which shall be considered equivalent to NFPA 13D. 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 supply 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.

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

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 SOURCE

RANGE 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.

  1. Sprinklers shall not be located at distances less than the minimum table distance unless the sprinkler listing allows a lesser distance.
  2. Distances shall be measured in a straight line from the nearest edge of the heat source to the nearest edge of the sprinkler.
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.
Sprinkler coverage requirements and sprinkler obstruction requirements shall be in accordance with Sections P2904.2.4.1 and P2904.2.4.2.
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.
Sprinkler discharge shall not be blocked by obstructions unless additional sprinklers are installed to protect the obstructed area. Sprinkler separation from obstructions shall comply with the minimum distances specified in the sprinkler manufacturer's instructions.
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.
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.
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.
Painting, caulking or modifying of sprinklers shall be prohibited. Sprinklers that have been painted, caulked, modified or damaged shall be replaced with new sprinklers.
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.
Nonmetallic pipe and tubing, such as CPVC and PEX, shall be listed for use in residential fire sprinkler systems.

Nonmetallic pipe and tubing systems shall be protected from exposure to the living space by a layer of not less than 3/8 inch (9.5 mm) thick gypsum wallboard, 1/2 inch thick plywood (13 mm), 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.
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.
Piping beyond the service valve located at the beginning of the water distribution system shall not serve more than one dwelling.
A means to drain the sprinkler system shall be provided on the system side of the water distribution shutoff valve.
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.

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.

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.
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.
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.

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

  1. 7 minutes for dwelling units one story in height and less than 2,000 square feet (186 m2) in area.
  2. 10 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.

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.
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.
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 less 41 to 75 76 to 100 101 to 150 40 or less 41 to 75 76 to 100 101 to 150 40 or less 41 to 75 76 to 100 101 to 150
8 5.1 8.7 11.8 17.4 1.5 2.5 3.4 5.1 0.6 1.0 1.3 1.9
10 7.7 13.1 17.8 26.3 2.3 3.8 5.2 7.7 0.8 1.4 2.0 2.9
12 10.8 18.4 24.9 NP 3.2 5.4 7.3 10.7 1.2 2.0 2.7 4.0
14 14.4 24.5 NP NP 4.2 7.1 9.6 14.3 1.6 2.7 3.6 5.4
16 18.4 NP NP NP 5.4 9.1 12.4 18.3 2.0 3.4 4.7 6.9
18 22.9 NP NP NP 6.7 11.4 15.4 22.7 2.5 4.3 5.8 8.6
20 27.8 NP NP NP 8.1 13.8 18.7 27.6 3.1 5.2 7.0 10.4
22 NP NP NP NP 9.7 16.5 22.3 NP 3.7 6.2 8.4 12.4
24 NP NP NP NP 11.4 19.3 26.2 NP 4.3 7.3 9.9 14.6
26 NP NP NP NP 13.2 22.4 NP NP 5.0 8.5 11.4 16.9
28 NP NP NP NP 15.1 25.7 NP NP 5.7 9.7 13.1 19.4
30 NP NP NP NP 17.2 NP NP NP 6.5 11.0 14.9 22.0
32 NP NP NP NP 19.4 NP NP NP 7.3 12.4 16.8 24.8
34 NP NP NP NP 21.7 NP NP NP 8.2 13.9 18.8 NP
36 NP NP NP NP 24.1 NP NP NP 9.1 15.4 20.9 NP

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.
  1. 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.
  2. 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.
  3. 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)
8 2 1 1
10 3 1 1
12 4 1 1
14 5 2 1
16 7 3 1
18 9 4 1
20 11 4 2
22 NP 5 2
24 NP 5 2
26 NP 6 2
28 NP 6 2
30 NP 7 2
32 NP 7 3
34 NP 8 3
36 NP 8 3

For SI: 1 inch = 25.4 mm, 1 pound per square inch = 6.895 kPa, 1 gallon per minute = 0.063 L/s.
NP - Not permitted unless the actual water meter pressure loss is known.
  1. Table 2904.6.2(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.
  2. 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)
5 2.2
10 4.4
15 6.5
20 8.7
25 10.9
30 13
35 15.2
40 17.4

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)
15 20 25 30 35 40 45 50 55 60
Allowable length of pipe from service valve to farthest sprinkler (feet)
8 3/4 217 289 361 434 506 578 650 723 795 867
9 3/4 174 232 291 349 407 465 523 581 639 697
10 3/4 143 191 239 287 335 383 430 478 526 574
11 3/4 120 160 200 241 281 321 361 401 441 481
12 3/4 102 137 171 205 239 273 307 341 375 410
13 3/4 88 118 147 177 206 235 265 294 324 353
14 3/4 77 103 128 154 180 205 231 257 282 308
15 3/4 68 90 113 136 158 181 203 226 248 271
16 3/4 60 80 100 120 140 160 180 200 220 241
17 3/4 54 72 90 108 125 143 161 179 197 215
18 3/4 48 64 81 97 113 129 145 161 177 193
19 3/4 44 58 73 88 102 117 131 146 160 175
20 3/4 40 53 66 80 93 106 119 133 146 159
21 3/4 36 48 61 73 85 97 109 121 133 145
22 3/4 33 44 56 67 78 89 100 111 122 133
23 3/4 31 41 51 61 72 82 92 102 113 123
24 3/4 28 38 47 57 66 76 85 95 104 114
25 3/4 26 35 44 53 61 70 79 88 97 105
26 3/4 24 33 41 49 57 65 73 82 90 98
27 3/4 23 30 38 46 53 61 69 76 84 91
28 3/4 21 28 36 43 50 57 64 71 78 85
29 3/4 20 27 33 40 47 53 60 67 73 80
30 3/4 19 25 31 38 44 50 56 63 69 75
31 3/4 18 24 29 35 41 47 53 59 65 71
32 3/4 17 22 28 33 39 44 50 56 61 67
33 3/4 16 21 26 32 37 42 47 53 58 63
34 3/4 NP 20 25 30 35 40 45 50 55 60
35 3/4 NP 19 24 28 33 38 42 47 52 57
36 3/4 NP 18 22 27 31 36 40 45 49 54
37 3/4 NP 17 21 26 30 34 38 43 47 51
38 3/4 NP 16 20 24 28 32 36 40 45 49
39 3/4 NP 15 19 23 27 31 35 39 42 46
40 3/4 NP NP 18 22 26 29 33 37 40 44

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
  1. 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)
15 20 25 30 35 40 45 50 55 60
Allowable length of pipe from service valve to farthest sprinkler (feet)
8 1 806 1075 1343 1612 1881 2149 2418 2687 2955 3224
9 1 648 864 1080 1296 1512 1728 1945 2161 2377 2593
10 1 533 711 889 1067 1245 1422 1600 1778 1956 2134
11 1 447 586 745 894 1043 1192 1341 1491 1640 1789
12 1 381 508 634 761 888 1015 1142 1269 1396 1523
13 1 328 438 547 657 766 875 985 1094 1204 1313
14 1 286 382 477 572 668 763 859 954 1049 1145
15 1 252 336 420 504 588 672 756 840 924 1008
16 1 224 298 373 447 522 596 671 745 820 894
17 1 200 266 333 400 466 533 600 666 733 799
18 1 180 240 300 360 420 479 539 599 659 719
19 1 163 217 271 325 380 434 488 542 597 651
20 1 148 197 247 296 345 395 444 493 543 592
21 1 135 180 225 270 315 360 406 451 496 541
22 1 124 165 207 248 289 331 372 413 455 496
23 1 114 152 190 228 267 305 343 381 419 457
24 1 106 141 176 211 246 282 317 352 387 422
25 1 98 131 163 196 228 261 294 326 359 392
26 1 91 121 152 182 212 243 273 304 334 364
27 1 85 113 142 170 198 226 255 283 311 340
28 1 79 106 132 159 185 212 238 265 291 318
29 1 74 99 124 149 174 198 223 248 273 298
30 1 70 93 116 140 163 186 210 233 256 280
31 1 66 88 110 132 153 175 197 219 241 263
32 1 62 83 103 124 145 165 186 207 227 248
33 1 59 78 98 117 137 156 176 195 215 234
34 1 55 74 92 111 129 148 166 185 203 222
35 1 53 70 88 105 123 140 158 175 193 210
36 1 50 66 83 100 116 133 150 166 183 199
37 1 47 63 79 95 111 126 142 158 174 190
38 1 45 60 75 90 105 120 135 150 165 181
39 1 43 57 72 86 100 115 129 143 158 172
40 1 41 55 68 82 96 109 123 137 150 164

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.
  1. 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)
15 20 25 30 35 40 45 50 55 60
Allowable length of pipe from service valve to farthest sprinkler (feet)
8 3/4 348 465 581 697 813 929 1045 1161 1278 1394
9 3/4 280 374 467 560 654 747 841 934 1027 1121
10 3/4 231 307 384 461 538 615 692 769 845 922
11 3/4 193 258 322 387 451 515 580 644 709 773
12 3/4 165 219 274 329 384 439 494 549 603 658
13 3/4 142 189 237 284 331 378 426 473 520 568
14 3/4 124 165 206 247 289 330 371 412 454 495
15 3/4 109 145 182 218 254 290 327 363 399 436
16 3/4 97 129 161 193 226 258 290 322 354 387
17 3/4 86 115 144 173 202 230 259 288 317 346
18 3/4 78 104 130 155 181 207 233 259 285 311
19 3/4 70 94 117 141 164 188 211 234 258 281
20 3/4 64 85 107 128 149 171 192 213 235 256
21 3/4 58 78 97 117 136 156 175 195 214 234
22 3/4 54 71 89 107 125 143 161 179 197 214
23 3/4 49 66 82 99 115 132 148 165 181 198
24 3/4 46 61 76 91 107 122 137 152 167 183
25 3/4 42 56 71 85 99 113 127 141 155 169
26 3/4 39 52 66 79 92 105 118 131 144 157
27 3/4 37 49 61 73 86 98 110 122 135 147
28 3/4 34 46 57 69 80 92 103 114 126 137
29 3/4 32 43 54 64 75 86 96 107 118 129
30 3/4 30 40 50 60 70 81 91 101 111 121
31 3/4 28 38 47 57 66 76 85 95 104 114
32 3/4 27 36 45 54 63 71 80 89 98 107
33 3/4 25 34 42 51 59 68 76 84 93 101
34 3/4 24 32 40 48 56 64 72 80 88 96
35 3/4 23 30 38 45 53 61 68 76 83 91
36 3/4 22 29 36 43 50 57 65 72 79 86
37 3/4 20 27 34 41 48 55 61 68 75 82
38 3/4 20 26 33 39 46 52 59 65 72 78
39 3/4 19 25 31 37 43 50 56 62 68 74
40 3/4 18 24 30 35 41 47 53 59 65 71

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.
  1. 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)
15 20 25 30 35 40 45 50 55 60
Allowable length of pipe from service valve to farthest sprinkler (feet)
8 1 1049 1398 1748 2098 2447 2797 3146 3496 3845 4195
9 1 843 1125 1406 1687 1968 2249 2530 2811 3093 3374
10 1 694 925 1157 1388 1619 1851 2082 2314 2545 2776
11 1 582 776 970 1164 1358 1552 1746 1940 2133 2327
12 1 495 660 826 991 1156 1321 1486 1651 1816 1981
13 1 427 570 712 854 997 1139 1281 1424 1566 1709
14 1 372 497 621 745 869 993 1117 1241 1366 1490
15 1 328 437 546 656 765 874 983 1093 1202 1311
16 1 291 388 485 582 679 776 873 970 1067 1164
17 1 260 347 433 520 607 693 780 867 954 1040
18 1 234 312 390 468 546 624 702 780 858 936
19 1 212 282 353 423 494 565 635 706 776 847
20 1 193 257 321 385 449 513 578 642 706 770
21 1 176 235 293 352 410 469 528 586 645 704
22 1 161 215 269 323 377 430 484 538 592 646
23 1 149 198 248 297 347 396 446 496 545 595
24 1 137 183 229 275 321 366 412 458 504 550
25 1 127 170 212 255 297 340 382 425 467 510
26 1 118 158 197 237 276 316 355 395 434 474
27 1 111 147 184 221 258 295 332 368 405 442
28 1 103 138 172 207 241 275 310 344 379 413
29 1 97 129 161 194 226 258 290 323 355 387
30 1 91 121 152 182 212 242 273 303 333 364
31 1 86 114 143 171 200 228 257 285 314 342
32 1 81 108 134 161 188 215 242 269 296 323
33 1 76 102 127 152 178 203 229 254 280 305
34 1 72 96 120 144 168 192 216 240 265 289
35 1 68 91 114 137 160 182 205 228 251 273
36 1 65 87 108 130 151 173 195 216 238 260
37 1 62 82 103 123 144 165 185 206 226 247
38 1 59 78 98 117 137 157 176 196 215 235
39 1 56 75 93 112 131 149 168 187 205 224
40 1 53 71 89 107 125 142 160 178 196 214

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.
  1. Flow rate from Section P2904.4.2.
TABLE P2904.6.2(8)
ALLOWABLE PIPE LENGTH FOR 3/4-INCH PEX TUBING
SPRINKLER
FLOW RATEa
(gpm)
WATER
DISTRIBUTION
SIZE (inch)
AVAILABLE PRESSURE - Pt (psi)
15 20 25 30 35 40 45 50 55 60
Allowable length of pipe from service valve to farthest sprinkler (feet)
8 3/4 93 123 154 185 216 247 278 309 339 370
9 3/4 74 99 124 149 174 199 223 248 273 298
10 3/4 61 82 102 123 143 163 184 204 225 245
11 3/4 51 68 86 103 120 137 154 171 188 205
12 3/4 44 58 73 87 102 117 131 146 160 175
13 3/4 38 50 63 75 88 101 113 126 138 151
14 3/4 33 44 55 66 77 88 99 110 121 132
15 3/4 29 39 48 58 68 77 87 96 106 116
16 3/4 26 34 43 51 60 68 77 86 94 103
17 3/4 23 31 38 46 54 61 69 77 84 92
18 3/4 21 28 34 41 48 55 62 69 76 83
19 3/4 19 25 31 37 44 50 56 62 69 75
20 3/4 17 23 28 34 40 45 51 57 62 68
21 3/4 16 21 26 31 36 41 47 52 57 62
22 3/4 NP 19 24 28 33 38 43 47 52 57
23 3/4 NP 17 22 26 31 35 39 44 48 52
24 3/4 NP 16 20 24 28 32 36 40 44 49
25 3/4 NP NP 19 22 26 30 34 37 41 45
26 3/4 NP NP 17 21 24 28 31 35 38 42
27 3/4 NP NP 16 20 23 26 29 33 36 39
28 3/4 NP NP 15 18 21 24 27 30 33 36
29 3/4 NP NP NP 17 20 23 26 28 31 34
30 3/4 NP NP NP 16 19 21 24 27 29 32
31 3/4 NP NP NP 15 18 20 23 25 28 30
32 3/4 NP NP NP NP 17 19 21 24 26 28
33 3/4 NP NP NP NP 16 18 20 22 25 27
34 3/4 NP NP NP NP NP 17 19 21 23 25
35 3/4 NP NP NP NP NP 16 18 20 22 24
36 3/4 NP NP NP NP NP 15 17 19 21 23
37 3/4 NP NP NP NP NP NP 16 18 20 22
38 3/4 NP NP NP NP NP NP 16 17 19 21
39 3/4 NP NP NP NP NP NP NP 16 18 20
40 3/4 NP NP NP NP NP NP NP 16 17 19

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.
  1. Flow rate from Section P2904.4.2.
TABLE P2904.6.2(9)
ALLOWABLE PIPE LENGTH FOR 1-INCH PEX TUBING
SPRINKLER
FLOW RATEa
(gpm)
WATER
DISTRIBUTION
SIZE (inch)
AVAILABLE PRESSURE - Pt (psi)
15 20 25 30 35 40 45 50 55 60
Allowable length of pipe from service valve to farthest sprinkler (feet)
8 1 314 418 523 628 732 837 941 1046 1151 1255
9 1 252 336 421 505 589 673 757 841 925 1009
10 1 208 277 346 415 485 554 623 692 761 831
11 1 174 232 290 348 406 464 522 580 638 696
12 1 148 198 247 296 346 395 445 494 543 593
13 1 128 170 213 256 298 341 383 426 469 511
14 1 111 149 186 223 260 297 334 371 409 446
15 1 98 131 163 196 229 262 294 327 360 392
16 1 87 116 145 174 203 232 261 290 319 348
17 1 78 104 130 156 182 208 233 259 285 311
18 1 70 93 117 140 163 187 210 233 257 280
19 1 63 84 106 127 148 169 190 211 232 253
20 1 58 77 96 115 134 154 173 192 211 230
21 1 53 70 88 105 123 140 158 175 193 211
22 1 48 64 80 97 113 129 145 161 177 193
23 1 44 59 74 89 104 119 133 148 163 178
24 1 41 55 69 82 96 110 123 137 151 164
25 1 38 51 64 76 89 102 114 127 140 152
26 1 35 47 59 71 83 95 106 118 130 142
27 1 33 44 55 66 77 88 99 110 121 132
28 1 31 41 52 62 72 82 93 103 113 124
29 1 29 39 48 58 68 77 87 97 106 116
30 1 27 36 45 54 63 73 82 91 100 109
31 1 26 34 43 51 60 68 77 85 94 102
32 1 24 32 40 48 56 64 72 80 89 97
33 1 23 30 38 46 53 61 68 76 84 91
34 1 22 29 36 43 50 58 65 72 79 86
35 1 20 27 34 41 48 55 61 68 75 82
36 1 19 26 32 39 45 52 58 65 71 78
37 1 18 25 31 37 43 49 55 62 68 74
38 1 18 23 29 35 41 47 53 59 64 70
39 1 17 22 28 33 39 45 50 56 61 67
40 1 16 21 27 32 37 43 48 53 59 64

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.
  1. Flow rate from Section P2904.4.2.

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.

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.

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

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.

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.
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.
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.
When a detrimental condition exists, approved alternate materials or alternate routing shall be required.
Pipe and fittings used in the water-supply system shall have a maximum of 8 percent lead.
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.
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.
Mechanical joints shall be installed in accordance with the manufacturer's installation instructions.

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 minimum working pressure rating of 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

MATERIAL

STANDARD

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 CAN/CSA-B137.9M

Polyethylene (PE) plastic pipe

ASTM D 2104; ASTM D 2239; CSA-B137.1

Polyethylene (PE) plastic tubing

ASTM D 2737; CSA B137.1

Polypropylene (PP) plastic pipe or tubing

ASTM F 2389; CSA B137.11

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

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

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 a minimum of 5 feet (1524 mm), measured horizontally, of undisturbed or compacted earth or placed on a solid ledge at least 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 to at least 5 feet (1524 mm), horizontally from the sewer pipe centerline, on both sides of the crossing with pipe materials listed in Tables P2905.4, P3002.1(1), P3002.1(2) or P3002.2.

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 minimum pressure rating of 100 psi at 180°F (689 kPa at 82°C).

TABLE P2905.5
WATER DISTRIBUTION PIPE

MATERIAL

STANDARD

Brass pipe

ASTM B 43

Chlorinated polyvinyl chloride (CPVC) plastic pipe and tubing

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 (PEX) plastic tubing

ASTM F 876; ASTM F 877; CSA B137.5

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

Galvanized steel pipe

ASTM A 53

Polyethylene/aluminum/polyethylene (PE-AL-PE) composite pipe

ASTM F 1282

Polypropylene (PP) plastic pipe or tubing

ASTM F 2389; CSA B137.11

Stainless steel (Type 304/304L) pipe

ASTM A 312; ASTM A 778

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

MATERIAL

STANDARD

Acrylonitrile butadiene styrene (ABS) plastic

ASTM D 2468

Brass

ASTM F1974

Cast-iron

ASME B16.4; ASME B16.12

Chlorinated polyvinyl chloride (CPVC) plastic

ASSE 1061; ASTM D 2846; ASTM F 437; ASTM F 438;
ASTM F 439; CSA B137.6

Copper or copper alloy

ASSE 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 tubing

ASSE 1061; ASTM F 877; ASTM F 1807; ASTM F 1960; ASTM F 2080; ASTM F 2098; ASTM F 2159; ASTM F 2434; CSA B137.5

Gray iron and ductile iron

AWWA C110; AWWA C153

Malleable iron

ASME 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) plastic

ASTM D 2609; CSA B137.1

Polypropylene (PP) plastic pipe or tubing

ASTM F 2389; CSA B137.11

Polyvinyl chloride (PVC) plastic

ASTM D 2464; ASTM D 2466; ASTM D 2467; CSA B137.2;
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

Steel

ASME B16.9; ASME B16.11; ASME B16.28

Flexible water connectors, exposed to continuous pressure, shall conform to ASME A112.18.6. Access shall be provided to all flexible water connectors.
Joints and connections in the plumbing system shall be gas tight and water tight for the intended use or required test pressure.
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 are permitted in accordance with Section P2905.3.
Solvent-cemented joints shall comply with Sections P2905.9.1.1 through P2905.9.1.3.
Solvent cement for ABS plastic pipe conforming to ASTM D 2235 shall be applied to all joint surfaces.

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 is not 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.
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.
Joints between cross-linked polyethylene plastic tubing or fittings shall comply with Section P2905.9.1.4.1 or Section P2905.9.1.4.2.
Flared pipe ends shall be made by a tool designed for that operation.
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 installation instructions. PEX tubing shall be factory marked with the applicable standards for the fittings that the PEX manufacturer specifies for use with the tubing.
Joints between PP plastic pipe and fittings shall comply with Section P2905.10.1 or P2905.10.2.
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.
Mechanical and compression sleeve joints shall be installed in accordance with the manufacturer's installation instructions.
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.
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.
Joints between stainless steel pipe and fittings shall comply with Sections P2905.12.1 and P2905.12.2.
Mechanical joints shall be installed in accordance with the manufacturer's instructions.
Joint surfaces shall be cleaned. The joint shall be welded autogenously or with an approved filler metal in accordance with ASTM A 312.
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.
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 maximum of 0.2 percent lead. Fluxes shall conform to ASTM B 813.
Flared joints in water tubing shall be made with approved fittings. The tubing shall be reamed and then expanded with a flaring tool.
Joints within the building between copper pipe or CPVC tubing, in any combination with compatible outside diameters, are permitted to be made with the use of approved push-in mechanical fittings of a pressure-lock design.
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.
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.
Joints between different types of plastic pipe or between plastic pipe and other piping material shall be made with an approved adapter fitting.
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.
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.
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.
Pipe and tubing support shall conform to Section P2605.
Drinking water treatment units shall meet the requirements of NSF 42, NSF 44 or NSF 53.
Point-of-use reverse osmosis drinking water treatment units, designed for residential use, shall meet the requirements of NSF 58. 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.
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.
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