Raft, pile, pier and beam foundations

Also see:

4.4.5Services and drainage

Raft, pile, pier and beam foundations shall take account of new and existing services. Issues to be taken into account include:

  1. provision for new services
  2. adequate protection of existing services and drainage.

Provision for new services

Where services are to pass through, above or under foundations, openings should be provided using suitable ducts, sleeves or lintels that:

  • are detailed so as not to impair structural stability
  • do not affect the ability of the foundation to carry loads
  • make suitable provision to allow for movement
  • have sufficient space to maintain line and gradient of drainage where movement occurs.

Existing services and drainage

Existing services or drains should:

  • be supported and protected
  • be bridged, to prevent any load carrying
  • not be rigidly encased in concrete, masonry, etc.

Land drains should be diverted to a suitable outfall; other drains should be diverted or bridged.