If you are having a flat roof installed or getting your old roof replaced, then you have two main options in terms of insulation methods: warm or cold flat roofing. While in warm flat roofing the layer of insulation is positioned above the roofing rafters – making the roof and loft similar in temperature to the rest of the property – cold flat roofing is when the layer of insulation is placed between or under the roofing rafters – meaning the rafters and roof are left cold. Nowadays, warm flat roofing is the more common and popular option because it is energy-efficient, cost-effective and moisture-resistant.
Dealing with water vapour
One of the main reasons that warm flat roofing designs are growing in popularity is that they can handle the increased levels of water vapour in modern homes. Central heating, tumble drying, cooking, washing: all these things can mean that more moisture is being produced within the home. The design features a water vapour control layer beneath the insulation layer. This is sealed to make sure moisture can escape, reducing the risk of damp.
Warm flat roofing
As well as enabling moisture to escape efficiently, warm flat roofing is a simple, easy-to-implement, cost-effective and thermally-efficient option. Essentially, this design brings the roofing deck indoors, which means it stays warm and doesn’t suffer from the build-up of condensation associated with cold surfaces. It offers a long-lasting roofing insulation option that often provides cost savings on fuel bills for many years to come after installation.
Cold flat roofing
The advantages of cold flat roofing systems are that they are easy and affordable to install. If this design is used, then an independent ventilation system is required to ensure that any moisture can be removed from the property efficiently, in the absence of a ventilation layer.
Swapping your cold roof for a warm roof
If your property currently has a cold flat roof and you would like to update it with the warm system, this can be achieved. Usually, if the roof is in good condition, then the systems can simply be changed over – with existing elements of the cold roof being used for parts of the new one. If the roof is in need of repair, then it may be more cost-effective to completely replace the existing roof and fit the warm flat roofing system as part of the replacement.