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4.4 Variations or Patterns of Water Demand 137
Table 4.13 Required Fire Flow for Buildings
1
2
Area (ft )
Type of Building Construction
Type I-A 2 Type V-B 3 Fire
Noncombustible, Combustible, Flow Duration
Protected Unprotected (gpm) (h)
0–22,700 0–3,600 1,500
22,701–30,200 3,601–4,800 1,750
30,201–38,700 4,801–6,200 2,000
38,701–48,300 6,201–7,700 2,250 2
48,301–59,000 7,701–9,400 2,500
59,001–70,900 9,401–11,300 2,750
70,901–83,700 11,301–13,400 3,000
83,701–97,700 13,401–15,600 3,250 3
97,701–112,700 15,601–18,000 3,500
112,701–128,700 18,001–20,600 3,750
128,701–145,900 20,601–23,300 4,000
145,901–164,200 23,301–26,300 4,250
164,201–183,400 26,301–29,300 4,500
183,401–203,700 29,301–32,600 4,750
203,701–225,200 32,601–36,000 5,000
225,201–247,700 36,001–39,600 5,250
247,701–271,200 39,601–43,400 5,500
271,201–295,900 43,401–47,400 5,750
295,901–Greater 47,401–51,500 6,000 4
— 51,501–55,700 6,250
— 55,701–60,200 6,500
— 60,201–64,800 6,750
— 64,801–69,600 7,000
— 69,601–74,600 7,250
— 74,601–79,800 7,500
— 79,801–85,100 7,750
— 85,101–greater 8,000
1 The specified area shall be the area of the three largest successive floors.
2 Typically these are concrete-frame buildings made of noncombustible materials. The “A” stands for protected.
3 Typically these are wood-frame buildings. The “B” stands for unprotected. Conversion factors: 1 ft 0.0929 m , 2
2
1 gpm 3.785 L/min.
Source: Data from International Fire Code (ICC, 2006).

noncombustible materials. All of the building elements—structural frame, bearing walls,
floors, and roofs—are fire resistance rated. Type V-B construction is typically wood-
frame construction, which is very common because it does not require a fire rating.
The benefits of early fire suppression are acknowledged by the acceptance that the
firefighting water requirement can be reduced by 50% for one- and two-family dwellings
2
2
and by up to 75% for larger buildings (exceeding 3,600 ft or 344 m ) when buildings are
fitted with automatic sprinkler systems.
Standard fire requirements take into account probable loss of water from connections
broken in the excitement of a serious fire. Coincident draft of water for purposes other than
firefighting is rarely assumed to equal the maximum hourly rate. Depending on local con-
ditions, the maximum daily rate may be a reasonably safe assumption instead.