Recommended U-Values for Domestic Buildings

England – Current

New BuildExtensionRenovation
Wall0.180.280.3
Floor0.130.220.25
Pitched Roof – Ceiling Level0.130.160.16
Pitched Roof – Rafter level0.130.180.18
Flat Roof0.130.180.18

Scotland – Current

New BuildExtension*Renovation
Wall0.150.170.22
Floor0.130.150.18
Pitched Roof – Ceiling Level0.100.110.15
Pitched Roof – Rafter level0.100.130.18
Flat Roof0.100.130.18

*Value required is dependant upon existing structures performance.

Wales – Current

New BuildExtension*Renovation
Wall0.160.210.3
Floor0.110.180.25
Pitched Roof – Ceiling Level0.110.150.16
Pitched Roof – Rafter level0.110.150.18
Flat Roof0.110.150.18