Poss Heat Loss caused by air bricks in block & Beam construction

[Balou]

Hi. We have a real problem with a new build (cavity walls with PIR, block and beam floors with 150mm insulation) where a couple of ground floor room temps are struggling to get above 15 degrees when its around 2 degrees outside. We've had a couple of air pressure tests carried out which is revealing an issue with a lot of air circulating behind the dot and dab plaster boarded walls and there seems to be a link to where we have exterior air bricks for the block and beam floors. Im wondering if its possible that the internal 'periscope' fittings  haven't been installed properly and allowing cold air to bypass the insulation. Is this likely? If so does anyone have suggestions on how to test for the problem please? The rooms in question were supposed to be for an elderly parent and have been pretty much unusable throughout winter months since completion. Any suggestions would be much appreciated.

[SBMS]

2 hours ago, Balou said:

Hi. We have a real problem with a new build (cavity walls with PIR, block and beam floors with 150mm insulation) where a couple of ground floor room temps are struggling to get above 15 degrees when its around 2 degrees outside. We've had a couple of air pressure tests carried out which is revealing an issue with a lot of air circulating behind the dot and dab plaster boarded walls and there seems to be a link to where we have exterior air bricks for the block and beam floors. Im wondering if its possible that the internal 'periscope' fittings  haven't been installed properly and allowing cold air to bypass the insulation. Is this likely? If so does anyone have suggestions on how to test for the problem please? The rooms in question were supposed to be for an elderly parent and have been pretty much unusable throughout winter months since completion. Any suggestions would be much appreciated.

Have you tried getting a thermal camera and looking at where the heat is leaking?