Technical Booklet N Drainage·Page 17·Table 2.5
Minimum diameter for discharge stacks - Table 2.5
Table setting minimum stack diameters based on peak flow rate, with notes that 50 mm and 65 mm stacks cannot serve WCs, and 75 mm stacks are limited to 1 siphonic WC maximum.
Table 2.5 Minimum diameter for discharge stacks
Peak flow rate (litres/sec) | Min diameter (mm)
1.2 | 50(1)
2.1 | 65(1)
3.4(2) | 75
5.3 | 90
7.2 | 100
Notes:
(1) No WCs.
(2) Not more than 1 siphonic WC permitted.
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