Monday, 22 November 2010
More photos from Weeks 2 and 3 - a comment on cavity walls
More photos from the build here. I may add a couple more during this week. The one below (I can't get it to display correctly, sorry) shows the existing cavity wall insulation, which has become saturated due to water penetration from driving rain (we believe).
We are planning to suck out all the existing insulation with a super powerful, industrial vacuum cleaner. Although the cavity will only be providing a small portion of the total insulative value of the new wall, we want to minimise the risk of gaps, which could allow air movement within the wall. It this happened, the U-value would be badly compromised. The replacement insulation (Instabead Graphite K32) has a significantly lower claimed conductivity value (0.033W/mK) than the rockwool (0.045W/mK).