Warm Deck Flat Roof Vapour Barrier

It has transpired that there is no vapour control layer fitted.

Warm deck flat roof vapour barrier.

The buildup of a warm flat roof starts with a good vapour barrier followed by insulation then more decking or just the roofing materials depends on if you wa. Vapour control layers vcl. 22 jan 2010 messages. Discussion in roofing and guttering started by sam85 21 jul 2017.

The roof is an unventilated warm roof design finished with a single ply membrane. A vapour barrier will then need to be installed to reduce condensation in the roof structure. A vapour control layer is designed to catch this vapour preventing it from condensing on the insulation or elsewhere in the loft space or attic. This could be a 1000 gauge min polythene sheet.

With any warm flat roof detail such as this a vapour control layer should have been laid on top of the roof deck underneath the insulation. I am having an extension built and my builder is constructing the flat warm deck roof in the following way. To use epdm for a warm deck flat roof construction solid closed cell roof insulation such as kingspan or celotex should be placed on top of the roof deck rather than in between the rafters. We provide a vapour control layer for flat roof installations as well as heavy duty vapour control layers for a warm flat roof.

Great videos thanks for sharing. I was looking to use this vapour barrier from screwfix but not sure if it s suitable for the job it only mentions underfloor heating and laminate flooring in the description. If this has not been done then we would recommend that you install one underneath the joists before the plasterboard goes up. Warm deck flat roof vapour barrier.

Poly to the underside of joists. I m in the process of building a warm flat roof for a garden room and need to put down a vapour barrier between the sub deck and insulation. The architect plans stated requirement for a vapour control layer below the insulation or a 3 in 1 insulation board including vapour control layer and an additional foil backed plasterboard.