Warm Or Cold Deck Roof

It is universally recommended that cold deck flat roof construction should be avoided.
Warm or cold deck roof. 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. 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. What is a warm roof or a cold roof. Warm roof insulation ensures the entire roof structure is insulated meaning a warm deck roof is more energy efficient than a cold roof.
In building construction roof pitch is a numerical measure of the steepness of a roof. The cold deck method works well when constructed correctly and in correct. 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. The layer of insulation is essentially placed outside of the roof.
These gaps help warm moist air escape before condensing on the cold deck above. A warm roof building will make the entire structure of the building warm in an attempt to avoid any cold bridging. Warm deck flat roof. You create a warm roof or a cold roof simply by applying the layers of the roof in a different order.
Ventilation is required for these roofs. 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. 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. 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.
The thermal efficiency isn t as good as with warm roof. The breakdown warm roof vs cold roof. 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. The solution warm deck insulation.
There are typically two different ways to insulate a roof a warm roof and a cold roof. This system is called warm deck insulation and eradicates the condensation and venting issues associated with the cold deck system. Introduction warm cold roofs this guidance offers guidance on the difference benefits between warm and cold roofs. Fortunately these days there is a better form of insulation available for your flat roof.
Guidance advice on.