• In a warm roof the principal insulation is immediately below the roof covering
  • The structural deck, any voids and the ceiling are at a temperature close to that of the building’s interior
  • Condensation control is achieved by using a vapour control layer (VCL) on the warm side of the insulation
  • The amount of insulation should be enough to maintain the VCL above dewpoint temperature
  • Warm roof voids are not ventilated
  • Condensation can be calculated to BS 6229 and BS 5250
warm roof


Sika Liquid Plastics launched its built up roof system in 2004, which signalled a revolution in roofing systems due to its completely flame free and heat free installation. Since then the market has evolved with more clients requiring cold applied options with improved workability.

Traditional methods of application for roofing systems can require temperatures in excess of +500°C to +800°C using gas torches, bitumen boilers, and hot gas guns. Creating heat at these temperatures, along with the combustible materials usually found on roofs, is a potentially dangerous combination.

Our built-up roof system is completely cold applied, thus eliminating the need for any heat or naked flame on the roof. The full system has been tested in accordance with BS EN 13501-5 and BS 476-3 and has achieved a BROOF(t4) and EXT. F.AB respectively, allowing unrestricted use under the current building regulations.

Also, as with the liquid applied waterproof membrane, the whole system is easy to install with simple application to detail areas.