702.7 Hot and Tempered Water Distribution

Water supply piping shall be in accordance with Section 702.7.1 or Section 702.7.2. The flow rate through ¹/₄-inch (6.4 mm) tubing shall not exceed 0.5 gpm (1.9 Lpm). The flow rate through ⁵/₁₆-inch (7.9 mm) tubing shall not exceed 1 gpm (3.8 Lpm). The flow rate through ³/₈-inch (9.5 mm) tubing shall not exceed 1.5 gpm (5.7 Lpm).

The maximum allowable pipe length from the source of hot or tempered water to the termination of the fixture supply pipe shall be in accordance with the maximum pipe length columns in Tables 702.7.2(2) through 702.7.2(10), as appropriate for the type of pipe to be installed. Where the type of pipe to be installed is unknown or the type of pipe is not covered by Tables 702.7.2(2) through 702.7.2(10), Table 702.7.2(1) shall be used for design purposes. Where the length contains more than one size of pipe, the largest size shall be used for determining the maximum allowable length of the pipe in the tables.

The water volume in the piping shall be calculated in accordance with Section 702.7.2.1. The maximum volume of hot or tempered water in the piping to public lavatory faucets, metering or nonmetering, shall be 2 ounces (0.06 L). For fixtures other than public lavatory faucets, the maximum volume shall be 64 ounces (1.89 L) for hot or tempered water from a water heater or boiler; and 24 ounces (0.7 L) for hot or tempered water from a circulation loop pipe or an electrically heat-traced pipe. The water volume in the piping shall be calculated in accordance with Section 702.7.2.1.

TABLE 702.7.2(1) VOLUME AND MAXIMUM LENGTH OF PIPE OR TUBE OF A TYPE UNKNOWN OR NOT COVERED^b

NOMINAL PIPE OR TUBE SIZE (inch)	LIQUID OUNCES PER FOOT OF LENGTH	MAXIMUM PIPE OR TUBE LENGTH
		System without a circulation loop or heat-traced line (feet)	System with a circulation loop or heat-traced line (feet)	Lavatory faucets — public (metering and nonmetering) (feet)
1/4a	0.33	50	16	6
5/16a	0.5	50	16	4
3/8a	0.75	50	16	3
1/2	1.5	43	16	2
5/8	2	32	12	1
3/4	3	21	8	0.5
7/8	4	16	6	0.5
1	5	13	5	0.5
11/4	8	8	3	0.5
11/2	11	6	2	0.5
2 or larger	18	4	1	0.5

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 3.785 L/m, 1 ounce = 29.6 ml.

a. The flow rate for 1/4-inch size pipe or tube is limited to 0.5 gallons per minute; for 5/16-inch size, it is limited to 1 gpm; for 3/8-inch size, it is limited to 1.5 gpm.

b. Not covered means pipe or tube types not covered by Tables 702.7.2(2) through 702.7.2(10).

TABLE 702.7.2(2) VOLUME AND MAXIMUM LENGTH OF TYPE K COPPER TUBING

NOMINAL PIPE OR TUBE SIZE (inch)	LIQUID OUNCES PER FOOT OF LENGTH	MAXIMUM TUBE LENGTH
		System without a circulation loop or heat-traced line (feet)	System with a heat-traced line (feet)	Lavatory faucets — public (metering and nonmetering) (feet)
3/8a	0.84	44.6	14.3	2.7
1/2	1.45	44.5	16.6	2.1
3/4	2.90	21.7	8.3	0.5
1	5.17	12.6	4.8	0.5
11/4	8.09	7.9	3.0	0.5
11/2	11.45	5.8	1.9	0.5
2 or larger	20.04	3.6	0.9	0.4

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 3.785 L/m, 1 ounce = 29.6 ml.

a. The flow rate for 3/8-inch size is limited to 1.5 gallons per minute.

TABLE 702.7.2(3) VOLUME AND MAXIMUM LENGTH OF TYPE L COPPER TUBING

NOMINAL PIPE OR TUBE SIZE (inch)	LIQUID OUNCES PER FOOT OF LENGTH	MAXIMUM TUBE LENGTH
		System without a circulation loop or heat-traced line (feet)	System with a circulation loop or heat-traced line (feet)	Lavatory faucets — public (metering and nonmetering) (feet)
3/8a	0.97	38.7	12.4	2.3
1/2	1.55	41.6	15.5	1.9
3/4	3.22	19.6	7.5	0.5
1	5.49	11.8	4.6	0.5
11/4	8.38	7.6	2.9	0.5
11/2	11.83	5.6	1.9	0.5
2 or larger	20.58	3.5	0.9	0.4

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 3.785 L/m, 1 ounce = 29.6 ml.

a. The flow rate for 3/8-inch size is limited to 1.5 gpm.

TABLE 702.7.2(4) VOLUME AND MAXIMUM LENGTH OF TYPE M COPPER TUBING

NOMINAL PIPE OR TUBE SIZE (inch)	LIQUID OUNCES PER FOOT OF LENGTH	MAXIMUM TUBE LENGTH
		System without a circulation loop or heat-traced line (feet)	System with a circulation loop or heat-traced line (feet)	Lavatory faucets — public (metering and nonmetering) (feet)
3/8a	1.06	35.4	11.3	2.1
1/2	1.69	38.2	14.2	1.8
3/4	3.43	18.4	7.0	0.4
1	5.81	11.2	4.3	0.4
11/4	8.70	7.4	2.8	0.5
11/2	12.18	5.4	1.8	0.5
2 or larger	21.08	3.4	0.9	0.4

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 3.785 L/m, 1 ounce = 29.6 ml.

a. The flow rate for 3/8-inch size is limited to 1.5 gpm.

TABLE 702.7.2(5) VOLUME AND MAXIMUM LENGTH OF CPVC TUBING, CTS^a

NOMINAL PIPE OR TUBE SIZE (inch)	LIQUID OUNCES PER FOOT OF LENGTH	MAXIMUM TUBE LENGTH
		System without a circulation loop or heat-traced line (feet)	System with a circulation loop or heat-traced line (feet)	Lavatory faucets — public (metering and nonmetering) (feet)
1/2	1.25	51.6	19.2	2.4
3/4	2.67	23.6	9.0	0.6
1	4.43	14.7	5.6	0.6
11/4	6.61	9.7	3.6	0.6
11/2	9.22	7.2	2.4	0.6
2 or larger	15.79	4.6	1.1	0.6

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 3.785 L/m, 1 ounce = 29.6 ml.

a. Copper tube size outside diameter dimension and SDR 11.

TABLE 702.7.2(6) VOLUME AND MAXIMUM LENGTH OF CPVC PIPE, SCHEDULE 40

NOMINAL PIPE OR TUBE SIZE (inch)	LIQUID OUNCES PER FOOT OF LENGTH	MAXIMUM TUBE LENGTH
		System without a circulation loop or heat-traced line (feet)	System with a circulation loop or heat-traced line (feet)	Lavatory faucets — public (metering and nonmetering) (feet)
3/8a	1.17	32.1	10.3	1.9
1/2	1.89	34.1	12.7	1.6
3/4	3.58	17.6	6.7	0.4
1	5.53	11.8	4.5	0.5
11/4	9.66	6.6	2.5	0.4
11/2	13.20	5.0	1.7	0.4
2 or larger	21.88	3.3	0.8	0.4

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 3.785 L/m, 1 ounce = 29.6 ml.

a. The flow rate for 3/8-inch size is limited to 1.5 gpm.

TABLE 702.7.2(7) VOLUME AND MAXIMUM LENGTH OF CPVC PIPE, SCHEDULE 80

NOMINAL PIPE OR TUBE SIZE (inch)	LIQUID OUNCES PER FOOT OF LENGTH	MAXIMUM TUBE LENGTH
		System without a circulation loop or heat-traced line (feet)	System with a circulation loop or heat-traced line (feet)	Lavatory faucets — public (metering and nonmetering) (feet)
3/8a	0.86	43.6	14.0	2.6
1/2	1.46	44.2	16.4	2.1
3/4	2.74	23.0	8.8	0.5
1	4.56	14.3	5.5	0.5
11/4	8.24	7.8	2.9	0.5
11/2	11.38	5.8	1.9	0.5
2 or larger	19.11	3.8	0.9	0.5

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 3.785 L/m, 1 ounce = 29.6 ml.

a. The flow rate for 3/8-inch size is limited to 1.5 gpm.

TABLE 702.7.2(8) VOLUME AND MAXIMUM LENGTH OF PE-AL-PE TUBING

NOMINAL PIPE OR TUBE SIZE (inch)	LIQUID OUNCES PER FOOT OF LENGTH	MAXIMUM TUBE LENGTH
		System without a circulation loop or heat-traced line (feet)	System with a circulation loop or heat-traced line (feet)	Lavatory faucets — public (metering and nonmetering) (feet)
3/8a	0.63	59.5	19.0	3.6
1/2	1.31	49.2	18.3	2.3
3/4	3.39	18.6	7.1	0.4
1	5.56	11.7	4.5	0.4
11/4	8.49	7.5	2.8	0.5
11/2	13.88	4.8	1.6	0.4
2 or larger	21.48	3.4	0.8	0.4

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 3.785 L/m, 1 ounce = 29.6 ml.

a. The flow rate for 3/8-inch size is limited to 1.5 gpm.

TABLE 702.7.2(9) VOLUME AND MAXIMUM LENGTH OF PEX AND PE-RT TUBING, CTS^b

NOMINAL PIPE OR TUBE SIZE (inch)	LIQUID OUNCES PER FOOT OF LENGTH	MAXIMUM TUBE LENGTH
		System without a circulation loop or heat-traced line (feet)	System with a circulation loop or heat-traced line (feet)	Lavatory faucets — public (metering and nonmetering) (feet)
3/8a	0.6	58.6	18.8	3.5
1/2	1.18	54.7	20.3	2.5
3/4	2.35	26.8	10.2	0.6
1	3.91	16.6	6.4	0.6
11/4	5.81	11.0	4.1	0.7
11/2	8.09	8.2	2.7	0.7
2 or larger	13.86	5.2	1.3	0.6

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 3.785 L/m, 1 ounce = 29.6 ml.

a. The flow rate for 3/8-inch size is limited to 1.5 gpm.

b. Copper tube size outside diameter dimension and SDR 9, for both PEX and PE-RT types of tubing.

TABLE 702.7.2(10) VOLUME AND MAXIMUM LENGTH OF PEX-AL-PEX TUBING

NOMINAL PIPE OR TUBE SIZE (inch)	LIQUID OUNCES PER FOOT OF LENGTH	MAXIMUM TUBE LENGTH
		System without a circulation loop or heat-traced line (feet)	System with a circulation loop or heat-traced line (feet)	Lavatory faucets — public (metering and nonmetering) (feet)
3/8a	0.63	59.5	19.0	3.6
1/2	1.31	49.2	18.3	2.3
3/4	3.39	18.6	7.1	0.4
1	5.56	11.7	4.5	0.4
11/4	8.49	7.5	2.8	0.5
11/2	13.88	4.8	1.6	0.4
2 or larger	21.48	3.4	0.8	0.4

For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 gallon per minute = 3.785 L/m, 1 ounce = 29.6 ml.

a. The flow rate for 3/8-inch size is limited to 1.5 gpm.

The volume shall be the sum of the internal volumes of pipe, fittings, valves, meters and manifolds between the source of hot water and the termination of the fixture supply pipe. The volume shall be determined from the liquid ounces per foot column of Tables 702.7.2(2) through 702.7.2(10) as appropriate for the type of pipe. Where the type of pipe is unknown or the type of pipe is not covered by Tables 702.7.2(2) through 702.7.2(10), Table 702.7.2(1) shall be used to determine the volume. The volume contained within fixture shutoff valves, flexible water supply connectors to a fixture fitting, or within a fixture fitting shall not be included in the water volume determination. Where hot or tempered water is supplied by a circulation loop pipe or an electrically heat-traced pipe, the volume shall include the portion of the fitting on the source pipe that supplies water to the fixture.