Knauf Insulation Rafter Insulation
Pitched Roof Rafter Level (Warm Roof)
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Insulation is friction-fitted between rafters, with the option to underline the rafters with a layer of non-combustible Rocksilk® RS45 to further enhance thermal performance.

As rooms-in-roof are usually used as bedrooms, acoustic performance and sound reduction of external noise should be considered in addition to thermal performance.

Our insulation solutions for warm roofs provide thermal efficiency, whilst also contributing to acoustic performance.




Why Mineral Wool?

  • Mineral Wool provides the best combination of thermal, fire safety and acoustic performance.

  • Mineral Wool is easier to install correctly than other insulants such as rigid boards because it adapts to any slight imperfections in the substrate and knits together, eliminating any air gaps. Evidence shows the absence of air gaps is crucial to achieving real performance in the relevant application.

Download our Solutions Guide    U-value Tables

For any U-value calculations for alternative construction build-ups, please contact our Technical Support Team on 01744 766 666 or visit our online tool here.

For written U-value calculations, please email details of your full construction build-up to [email protected] and we will respond accordingly to meet your requirements.