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What U-Values should you target for your extension?

Chris Brookman
Member Admin

U-values show how much heat loss you get through your walls for a given temperature difference between inside and outside and the lower the number, the less heat you lose. The building control minimums for the roofs on extensions are quite respectable but when it comes to the walls we feel they’re somewhat lacking so we’d suggest the following:-

Roofs - Maximum of 0.18 W/m2K

Walls - Maximum of 0.20 W/m2K

Ground floors - Maximum of 0.22 W/m2K

These values will help you build spaces that are both warm in winter, cool in summer and quiet, even in urban locations.

Topic starter Posted : 09/03/2021 6:12 pm

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