Warm Or Cold Deck Roof

Warm roof insulation ensures the entire roof structure is insulated meaning a warm deck roof is more energy efficient than a cold roof.

Warm or cold deck roof.

These gaps help warm moist air escape before condensing on the cold deck above. Cold deck roof a cold deck roof is where the insulation is placed between the joists rafters or in between the ceiling joists in the case of a pitch roof. This system is called warm deck insulation and eradicates the condensation and venting issues associated with the cold deck system. This cold deck construction is considered problematic in the humid temperate climate of the uk where the effective ventilation of restricted roof voids may be impractical particularly in sheltered built up areas.

Fortunately these days there is a better form of insulation available for your flat roof. Pencast cold roof construction pencast warm roof construction it is perhaps surprising and certainly unfortunate that some building professionals and contractors are under a misapprehension as to the precise requirements in order to achieve warm roof and or cold roof construction. The thermal efficiency isn t as good as with warm roof. In a cold roof the insulation is applied between the rafters but in a warm roof the insulation is applied on top of the existing roof surface.

By moving the insulation to the outside of the structure the roof deck is effectively brought inside which results in a warm deck hence the name this removes the the possibility of condensation forming on the underside of the deck and eliminates damp. The solution warm deck insulation. What is a warm roof or a cold roof. The insulation in a warm deck roof is installed immediately below the roof membrane on top of the roof deck usually with a vapour control layer underneath the insulation.

A warm roof building will make the entire structure of the building warm in an attempt to avoid any cold bridging. The layer of insulation is essentially placed outside of the roof. Namely the insulation layers. In building construction roof pitch is a numerical measure of the steepness of a roof.

Ventilation is required for these roofs. A cold flat roof insulation requires more work taking off old boards and replacing them and the roof surface. The breakdown warm roof vs cold roof. There are typically two different ways to insulate a roof a warm roof and a cold roof.

You create a warm roof or a cold roof simply by applying the layers of the roof in a different order. Contrasted with the cold deck roof this construction has a much lower risk of condensation as the void will be of a comparable temperature to the roof. The cold deck method works well when constructed correctly and in correct. It is universally recommended that cold deck flat roof construction should be avoided.

With an older cold deck flat roof vapour control is achieved by ensuring a gap of 25mm or more between the ceiling and the insulation layer and between the insulation layer and the deck above.