On Friday, I carried out an intermediate air pressure test on Daisy Bank Cottage near Kendal. The self-builder, Alex Burn of 4site has taken a pragmatic approach to his build – keeping the design as simple as possible and primarily using standard materials available through local builders merchants. The building is masonry construction and Alex has applied basic Passivhaus principles to the build. The result of the intermediate airtightness test is 0.29 ach @ 50Pa (compared to the Passivhaus threshold of 0.6 ach @ 50Pa).
To compare this to normal UK standards, the air permeability result is 0.32 m3/hm2 @ 50Pa – typically dwellings constructed to Part L 2013 onwards have to achieve an air permeability somewhere between 5 and 10 m3/hm2 @ 50Pa
Well done Alex!