Technical Booklet N Drainage·Page 16
Trap tail lengthening when using larger branch pipe
Where the larger branch pipe size is used and the diameter of the trap is not increased, the tail of the trap should be lengthened by 50 mm before increasing the diameter.
Where the larger branch pipe size is used and the diameter of the trap is not increased the tail of the trap should be lengthened by 50 mm before increasing the diameter
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