Warm Deck Flat Roof Definition

The vapour control layer is above the decking but below the insulation.

Warm deck flat roof definition.

The warm deck roof design is the modern method for flat roof construction and is preferred wherever this option is possible. In these cases a cold roof is a preferable alternative to warm roof insulation. Warm roof in a warm roof construction the principal insulation layer is placed above the structural decking resulting in the structural deck and support structure being at a temperature similar to that of the building interior. This results in the structural deck and its supports being at a temperature closer to that of the building s interior.

Warm deck roof a warm deck roof is where the insulation is placed on top of the rafters joists and the roof covering is then placed over the insulation. Warm deck flat roof the warm deck roof approach is different. A warm flat roof or a built up roof bur is one where all the insulation is above the joists deck making them part of the warm fabric of the building. This is as opposed to a cold roof in which the insulation is below or within the roof structure and so the roof structure is closer to the outside temperature.

Inverted warm deck roof the insulation boards in an inverted warm deck are laid over the structural deck and the waterproof covering. The insulation is placed below the waterproof covering and is either mechanically fixed or bitumen bonded on to the top of the deck. A warm deck roof is much easier to install offers great thermal performance but adds height to the flat roof. The insulation is immediately below the waterproofing layer.

As a result of the height difference warm roofs cannot be used on balconies and flat roofs extensions with doors leading onto the roof. On flat roofs a warm roof is one in which the insulation layer is laid on top of roof structure. No ventilation is required for these types. This completely removes the risk of condensation building up on the deck and timbers.