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The Ontario Building Code | Hydraulic Load

7.6.3.2. Hydraulic Load

(1) Except as provided in Sentence (3), the hydraulic load of a fixture or device that is listed in Table 7.6.3.2.A. shall be the number of fixture units given in the Table.

(2) Except as provided in Sentences (1) and (3), the hydraulic load of afixture that is not listed in Table 7.6.3.2.A. is the number of fixture units listed in Table 7.6.3.2.D.

(3) Where fixtures are supplied with both hot and cold water, the hydraulic loads for maximum separate demands shall be 75% of the hydraulic load of the fixture unitsgiven in Tables 7.6.3.2.A. and 7.6.3.2.D. when using a detailed engineering design method.

(4) The hydraulic load of urinals and water closets with direct flush valves shall be the number of fixture units listed in Tables 7.6.3.2.B. and 7.6.3.2.C.

Table 7.6.3.2.A.
Sizing of water Distribution Systems(1)(2)

Forming Part of Sentences 7.6.3.2.(1) to (3) and 7.6.3.4.(2), (3) and (5)

Item

Column 1

Column 2

Column 3

Column 4

Column 5

Column 6

Column 7

Column 8

Fixture or Device

Minimum Size of Supply pipe, in.

Private Use Hydraulic Load, fixture units

Public Use Hydraulic Load, fixture units

Cold

Hot

Total

Cold

Hot

Total

1.

Bathroom group with 6 LPF flush tank(3)

N/A

2.7

1.5

3.6

-

-

-

2.

Bathroom group with greater than 6 LPF flush tank(3)

N/A

4

3

6

-

-

-

3.

Bathroom group with more than 3 fixtures

-

-

-

(4)

-

-

-

4.

Bathtub with or without shower head

1/2

1

1

1.4

3

3

4

5.

Bathtub with ¾ in. spout

3/4

7.5

7.5

10

7.5

7.5

10

6.

Bedpan washer

1

-

-

-

7.5

7.5

10

7.

Bidet

3/8

1.5

1.5

2

-

-

-

8.

Clothes washer, 3.5 kg

1/2

1

1

1.4

2.25

2.25

3

9.

Clothes washer, 6.8 kg

1/2

-

-

-

3

3

4

10.

Clothes washer, commercial(5)

-

-

-

-

-

-

-

11.

Dental lavatory

3/8

-

-

-

1.5

1.5

2

12.

Dental unit, cuspidor

3/8

-

-

-

1

-

1

13.

Dishwasher, commercial(5)

-

-

-

-

-

-

-

14.

Dishwasher, domestic

3/8

-

1.4

1.4

-

-

-

15.

Drinking fountain or water cooler

3/8

-

-

-

0.25

-

0.25

16.

Hose bibb

1/2

2.5

-

2.5

2.5

-

2.5

17.

Hose bibb

3/4

3

-

3

6

-

6

18.

Hose bibb, combination hot and cold

1/2

1.9

1.9

2.5

1.9

1.9

2.5

19.

Lavatory, 8.3 L/min or less

3/8

0.5

0.5

0.7

1.5

1.5

2

20.

Lavatory, greater than 8.3 L/min

3/8

0.75

0.75

1

1.5

1.5

2

21.

shower head, 9.5 L/min or less per head

1/2

1

1

1.4

3

3

4

22.

shower head, greater than 9.5 L/min per head

1/2

1.5

1.5

2

3

3

4

23.

shower, spray, multi-head, fixture unit per head

(5)

1

1

1.4

3

3

4

24.

Sink, bar

3/8

0.75

0.75

1

1.5

1.5

2

25.

Sink, clinic service faucet

1/2

-

-

-

2.25

2.25

3

26.

Sink, clinic service with direct flush valve

1

-

-

-

6

-

6

27.

Sink, kitchen, commercial, per faucet

1/2

-

-

-

3

3

4

28.

Sink, kitchen, domestic, 8.3 L/min or less

3/8

1

1

1.4

1

1

1.4

29.

Sink, kitchen, domestic, greater than 8.3 L/min

3/8

1.5

1.5

2

1.5

1.5

2

30.

Sink, laboratory

3/8

-

-

-

1.5

1.5

2

31.

Sink, laundry (1 or 2 compartments)

3/8

1

1

1.4

1

1

1.4

32.

Sink, service or mop basin

1/2

-

-

-

2.25

2.25

3

33.

Sink, washup, per faucet

1/2

-

-

-

1.5

1.5

2

34.

urinal, with direct flush valve

3/4

(6)

-

(6)

(6)

-

(6)

35.

urinal, with flush tank

3/8

3

-

3

3

-

3

36.

urinal, with self-closing metering valve

1/2

2

-

2

4

-

4

37.

water closet, 6 LPF or less with flush tank

3/8

2.2

-

2.2

2.2

-

2.2

38.

water closet, greater than 6 LPF with flush tank

3/8

3

-

3

5

-

5

39.

water closet, with direct flush valve

1

(6)

-

(6)

(6)

-

(6)

Notes to Table 7.6.3.2.A.:

(1) The fixture unit values in this Table are not applicable in certain assembly occupancies because of surges in use by the occupants. For such occupancies, refer to specific design information.

(2) For fixtures not indicated in this Table, refer to Table 7.6.3.2.D.

(3) Bathroom groupis based on a ½ in. size bathtub supply pipe.

(4) Add additional fixture to the fixture load for bathroom group.

(5) Refer to the manufacturer’s recommendations.

(6) For fixture unit values for fixtures with direct flush valves, see Sentence 7.6.3.2.(4) and Tables 7.6.3.2.B. and 7.6.3.2.C.

Table 7.6.3.2.B.
Sizing of water Distribution Systems for urinals with Direct flush Valves

Forming Part of Sentences 7.6.3.2.(4) and 7.6.3.4.(5)

Item

Column 1

Number of Valves

Column 2

Individual Fixture Units Assigned in Decreasing Values

Column 3

Fixture Units in Accumulative Values(1)

1.

1

20

20

2.

2

15

35

3.

3

10

45

4.

4

8

53

5.

5 or more

5 each

58, plus 5 for each additional fixture in excess of 5

Notes to Table 7.6.3.2.B.:

(1) The accumulative fixture unit values are the total values to be used in conjunction with Table 7.6.3.2.A.

Table 7.6.3.2.C.
Sizing of water Distribution Systems for water Closets with Direct flush Valves

Forming Part of Sentences 7.6.3.2.(4) and 7.6.3.4.(5)

Item

Column 1

Number of Valves

Column 2

Individual Fixture Units Assigned in Decreasing Values

Column 3

Fixture Units in Accumulative Values(1)

1.

1

40

40

2.

2

30

70

3.

3

20

90

4.

4

15

105

5.

5 or more

10 for each public use, and 6 for each private use

115, plus 10 for each public use additional fixture in excess of 5, and 111, plus 6 for each private use additional fixture in excess of 5

Notes to Table 7.6.3.2.C.:

(1) The accumulative fixture unit values are the total values to be used in conjunction with Table 7.6.3.2.A.

Table 7.6.3.2.D.
Hydraulic Loads of Fixtures Not Listed in Table 7.6.3.2.A.

Forming Part of Sentences 7.6.3.2.(2) and (3) and 7.6.3.4.(5)

Item

Column 1

Column 2

Column 3

Size of Supply pipe, in.

Hydraulic Load, fixture units

Private Use

Public Use

1.

⅜

1

2

2.

½

2

4

3.

¾

3

6

4.

1

6

10