The Ontario Building Code | Hydraulic Loads to Soil or Waste Pipes
7.4.10.6. Hydraulic Loads to soil or Waste pipes
(1) Except as provided in Sentence (2), the hydraulic load that is drained to every soil or waste stack shall conform to Table 7.4.10.6.
Table 7.4.10.6.
Maximum Permitted Hydraulic Load Drained to soil or Waste Stack
Forming Part of Sentence 7.4.10.6.(1)
| Item | Column 1 pipe Size, in. | Column 2 Maximum Hydraulic Load, fixture units | Column 3 Maximum Fixture Units Drained from any one Storey |
| 1. | 1 ¼ | 2 | 2 |
| 2. | 1 ½ | 8 | 5 |
| 3. | 2 | 24 | 10 |
| 4. | 3 | 102 | 18 |
| 5. | 4 | 540 | 100 |
| 6. | 5 | 1 400 | 250 |
| 7. | 6 | 2 900 | 500 |
| 8. | 8 | 7 600 | 830 |
| 9. | 10 | 15 000 | 2 700 |
| 10. | 12 | 26 000 | 4 680 |
| 11. | 15 | 50 000 | 9 000 |
(2) Where the nominally horizontal offset in a soil or waste stackis 1 500 mm or more, the hydraulic load that is served by it shall conform to Table 7.4.10.8.
(3) Vertical sanitary drainage pipe shall be designed to carry no more than 29% of its full capacity.