11.2.9 Insulation
Insulation shall be suitable for the intended use, correctly installed, and be of a suitable material and thickness to comply with Building Regulations and reduce the risk of surface and interstitial condensation.
Insulation should be:
- in accordance with the design
- installed correctly to minimise the risk of thermal bridging, surface, and interstitial condensation
- installed in accordance with the manufacturer’s recommendations.
The System Manual and design should include control measures to mitigate risk of slump of non-rigid insulation during transport and site installation.
Where insulation is to be installed to the external/cavity face of the frame, workmanship and tolerances of external walls, particularly at panel joints, should be maintained to minimise the risk of:
- reducing the width of clear cavities
- gaps between insulation boards
- ledges between insulation boards forming moisture traps.
Closed panel timber frame
Insulation to closed panel timber frame walls should be in accordance with Clause 6.2.15.
Structural insulated panels (SIPs)
Insulation to SIPs should be assessed as part of current certification by an appropriate independent technical approvals authority accepted by NHBC, as an integral part of the wall system.
Closed panel light steel frame
Insulation to closed panel light steel frame walls should be in accordance with Clause 6.10.17.
Last updated: 2nd January 2025