Lymington

A Warm Roof New Build Extension

This warm roof new build extension starts with a polythene vapour control layer. Condensation forms when warm, moist air rises and meets the colder surfaces above the insulation. Installed on the room side of the insulation, the vapour control layer stops that warm, moist air entering the structure.

We used 140mm PIR tissue-faced insulation, which suits both fully adhered and mechanically fixed systems, to achieve a U-value that meets the architect's specification. The U-value, or thermal transmittance, is the rate of heat transfer through a structure divided by the temperature difference across it, measured in W/m²K. The better insulated a structure is, the lower its U-value.

Evalon VSK 1.2mm membrane was self-adhered to the 140mm PIR insulation boards and the laps fully heat welded to create a waterproof roof covering, with the option of adding a green, blue or brown roof.