I have yet another new build house to air tightness test for defects this week. The householder moved in earlier this year, has noticed severe draughts in the last couple of weeks and has called me in to get to the bottom of the problem – I’m going to be doing an air tightness test and thermal imaging survey. The air tightness test will quantify the problem and the thermal images identify exactly where the issues are – this will give the householder concrete facts to then discuss the problem with the builder.
But why weren’t these identified by the house builder in the first place? Though an air tightness test is part of the Building Regs Part L1A, on a development, the builder needs to only test 3 units of each type or 50% of that dwelling type, whichever is the less. So depending on the nature of the development, only a handful of dwellings may be tested on a particular site.