CODES

ADOPTS WITH AMENDMENTS:

International Residential Code 2012 (IRC 2012)

Copyright

Minnesota Department of Labor and Industry

Important Disclaimer

Preface

Effective Use of the International Residential Code

Chapter 1 Scope and Administration

2015 Minnesota Building Code Administration

2015 Minnesota Provisions to the Minnesota State Building Code (Including Radon)

Minnesota Rules, Chapter 1309

Chapter 2 Definitions

Chapter 3 Building Planning

Chapter 4 Foundations

Chapter 5 Floors

Chapter 6 Wall Construction

Chapter 7 Wall Covering

Chapter 8 Roof-Ceiling Construction

Chapter 9 Roof Assemblies

Chapter 10 Chimneys and Fireplaces

Chapter 11 [Re] Energy Efficiency

Chapter 12 Mechanical Administration

Chapter 25 Plumbing Administration

Section P2904 Dwelling Unit Fire Sprinkler Systems

Chapter 34 General Requirements

Chapter 44 Referenced Standards

Appendix K Sound Transmission

Appendix L Permit Fees

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.

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 SOURCERANGE OF DISTANCE FROM HEAT SOURCE WITHIN WHICH
INTERMEDIATE TEMPERATURE SPRINKLERS ARE REQUIREDa, b (inches)
Fireplace, side of open or recessed fireplace12 to 36
Fireplace, front of recessed fireplace36 to 60
Coal and wood burning stove12 to 42
Kitchen range top9 to 18
Oven9 to 18
Vent connector or chimney connector9 to 18
Heating duct, not insulated9 to 18
Hot water pipe, not insulated6 to 12
Side of ceiling or wall warm air register12 to 24
Front of wall mounted warm air register18 to 36
Water heater, furnace or boiler3 to 6
Luminaire up to 250 watts3 to 6
Luminaire 250 watts up to 499 watts6 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. 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

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, PEX, and PE-RT 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-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.
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. 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.

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 7576 to 100101 to 15040 or less41 to 7576 to 100101 to 15040 or
less
41 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.

  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)
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.

NP—Not permitted unless the actual water meter pressure loss is known.

  1. 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.
  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)
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

  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)
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.

  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)
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.

  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)
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.

  1. 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.

  1. 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.

  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.

(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.
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