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What should you use to build the walls of your extension?

5 Posts
3 Users
Posts: 80
Member Admin
Topic starter

The main options would usually be masonry cavity construction or timber frame construction.

At Back to Earth we’d recommend using timber frame as we find it the most economical, practical and sustainable way to build and allows much more space efficient construction than masonry. You simply need to choose whether you’d prefer and rendered exterior or a timber/metal clad exterior. To see what we’d suggest click the relevant link below:-

Detail for timber framed walls with render - click here

Specification for rendered walls - click here

Detail for timber framed walls with cladding - click here

Specification for clad walls - click here

However, if for some reason you need to use masonry then we’d suggest fully filling the cavity with mineral or glass wool to maintain the best levels of insulation. Rigid boards such as PIR do not tend perform well in a masonry cavity and often do not achieve the standard they are designed to achieve, so we would not recommend them.

Posted : 09/03/2021 6:00 pm
Posts: 7

Chris ~ it seems the links in the above post no longer work...?

Posted : 12/02/2023 2:48 pm
Posts: 80
Member Admin
Topic starter

Thanks for the heads up on the link errors. Now fixed!

Posted : 13/02/2023 1:04 pm
Posts: 1

Thank you for your recommendations. It seems that at Back to Earth, you generally recommend timber frame construction for its economic, practical, and sustainable benefits, as well as its space efficiency compared to masonry construction. You offer options for both rendered exteriors and timber/metal clad exteriors for timber framed walls.

However, if masonry construction is required, you suggest fully filling the cavity with mineral or glass wool for optimal insulation. You advise against using rigid boards such as PIR in a masonry cavity, as they may not perform well and may not meet the desired insulation standards.

Posted : 17/07/2023 8:19 am
Posts: 80
Member Admin
Topic starter

Yes, that is what we would suggest.

Posted : 17/07/2023 8:30 am

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