In cold roof construction, the waterproof membrane is applied directly to the structural decking. This type of waterproofing requires adequate ventilation to be facilitated between the deck and the insulation layer to prevent moisture vapour rising upwards. Poor ventilation could be the cause of interstitial condensation in the roof structure.
The popularity of cold roof systems in the UK is on the decline, with Scottish Building Regulations not allowing cold roof design at all. Most specifiers therefore are encouraged to choose warm roof systems instead however cold roof systems have their advantages and place within flat roof construction.
