Above ground and below ground horizontal drainage pipes ...

because of the large pipe from a W.C. diameter (100mm) and because the drain is vented. Access points should be sited: (a) At a bend or change indirection (b) At a junction, unless each run can be cleared from an access point. (c) On or near the head of each drain run. (d) On long runs (e) At a change of pipe size. Sizing. 19.The soil & vent stack ................
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