What is a warm roof?

  • 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

Sika Liquid Plastics Solution

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.

The System Build Up

Vapour Control Layer

The full system includes S-Vap 5000E SA, which uses self adhesive technology and can be used as a temporary waterproofing layer - helping to protect the building from water ingress during installation. Therefore internal works can progress with minimum disruption to the build schedule.



Product Data Sheet


Decotherm is a high performance CFC/ HCFC free, PIR insulation with a glass fibre facing. It is available as flat board or tapered for those roofs that are not designed with a deck to falls.



Product Data Sheet


The Decotherm board is bonded using Decostik SP - a cold applied mid foaming single pack adhesive.



Product Data Sheet

Carrier Membrane

Sika Liquid Plastics Carrier Membrane SA is a high performance product that acts as temporary waterproofing for the insulation and provides a smooth, consistent surface for the application of the Decothane or Decaflex liquid waterproofing system.



Product Data Sheet

Liquid Waterproofing Membrane

Sika Liquid Plastics liquid applied membranes are high performance polyurethane coatings , which rapidly becomes resistant to rain damage. They cure to form a completely seamless, elastomeric membrane. Each system is fully reinforced with Sika Reemat Premium glass fibre matting. Systems are available to suit all client’s budget requirements.

Speak to an Expert

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