Technical Booklet N Drainage·Page 24·3.10
Concrete surround requirements for flexible pipes
Flexible pipes should be wrapped in polythene before being surrounded in concrete, with a minimum concrete surround thickness of 150 mm or the pipe diameter, whichever is greater.
Flexible pipes should be wrapped in polythene before surrounding in concrete. The minimum thickness of the concrete surround should be 150 mm or the diameter of the pipe whichever is the greater.
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