Underground Drainage Systems

combined drainage systems must have a 50mm minimum water seal. The table below is taken from BS EN 752 and provides guidance on minimum gradients for different size drains Solid wall perforated pipe 110mm solid wall perforated pipe is manufactured to the dimensional requirements of BS EN 1401-1. Pipe has two rows of slots that are 60mm apart and

  Pipe, Underground, Drainage, Drainage underground