Vapour Barrier Suspended Timber Floor Construction Detail

Once the timber floor boards have been laid temporary wedges should be inserted between the walls and the floor to maintain tight joints until the adhesive has set.

Vapour barrier suspended timber floor construction detail.

That leaves an opening to improve moisture management and airtightness by fitting a tyvek membrane and carefully sealing the gaps and joints. Some people and organisations will refer to the material that controls vapour movement as a vcl and some will call it a vapour barrier. Moisture management for suspended timber floor construction many suspended timber floor constructions have discontinuous insulation between the joists. Suspended timber floor as a requirement of the building regulations the structure should be protected against the growth of weeds and other plant life.

Once the wedges are removed they are replaced with strips of cork or polyethylene foam to act as a compressible filler and to help prevent cold bridging. However vapour barrier specification and details together with those for dpc and dpm are only mentioned in relation to the two generic floor construction types of suspended timber floors and concrete slab on ground in e2 as1 section 10 0 floors. A damp proof membrane or dpm is a waterproof barrier that s introduced between your sub floor and your wood floor. This barrier is intended to stop moisture passing from one to the other.

It is important to remember that no material is completely vapour proof so the term barrier can be slightly misleading. A vapour control layer with a low sd value that allows limited vapour transmission especially recommended on mineral wool wood fibre cellulose fibre and other breathable insulation materials. Vcls or vapour barriers will only reduce the vapour movement to an acceptable level. My plan is to remove the floor boards using some scaffolding netting stapled between the joists up and over up and over to hold some fibreglass insulation clean out any excess rubble and double check the air bricks.

At the turn of the 18th century when construction techniques moved from boarded floors installed directly on the ground to suspended timber floors over a ventilated chamber the innovation solved a significant problem. To answer your question introducing a vapour barrier to the underside of the floor joists would be a complete waste of time that is other than to assist in the air tightness of the building which is another bone of contention whereas introducing a vapour barrier over the top of the floor joists may well provide some long term benefits by reducing the amount of water vapour introduced to the. Hi i did just like to check my plan for installing some insulation in a timber joisted suspended wooden floor in a 1900 ish terraced house. Previously floor timbers had been prone to damp and rot thanks to their direct contact with the moist ground.