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  BU469 Damp-proof membranes to concrete slabs

BU469.jpgBRANZ recommends the installation of a DPM for all habitable (e.g. houses) and non-habitable (e.g. offices, garages) buildings constructed with a concrete slab on ground.

The purpose of a damp-proof membrane (DPM) or concrete underlay is to prevent water and water vapour passing from the ground through a concrete slab and into the interior of the building and damaging interior finishes, fittings and contents.

This bulletin outlines the specification and installation requirements for DPMs and covers:

  • moisture sources and action
  • types of DPM
  • correct installation, including laying the DPM, sealing joins and penetrations, construction considerations and edge treatment
  • polystyrene raft foundation systems.

Publication date: February 2006 Keywords: concrete, foundations, moisture