Can anyone help diagnose our cold room issue?

Newtown00

Hi All.

Hoping someone can give some advice. Our house is relativity warm except for rooms on one side. We had thermal imaging done and I've made some minor repairs that were recommended. Sealed around windows and under skirting. I've attached some of the thermal imaging photos. The external walls have been pumped by the previous owners and attic insulation is in good nick. One suggestion that I haven't got to, is to close off the top of the cavity wall (in the attic). Any advice hugely appreciated.

Coldest room is located to the front left of our house as you're looking at the front. The last photos are taken from inside the bedroom.

MicktheMan

Explain in detail what 'sealing' you have already done around the windows & skirting.

Does the cold side of the house you mention coincide with the prevailing wind side?

When the heating is switched off, does the house cool faster when it's very windy versus calm out?

My guess of what's going on; The external wall finish internally appears to be pb dot'n dabbed onto the innerleaf block wall (likely bare faced). There is significant air leakage from the cavity through the inner leaf block call to behind the pb and into the room through switches / sockets / element junctions such as floor to wall, holes in pb etc. If all the external walls in the house are finished the same then the same is happening to them also, it's just you don't notice it on the other side because you never notice warm air leaving, only cold air coming in.

Closing the cavity would have, imo, negligible, if any, impact.

Newtown00

Thanks a million for your post Mick.

I sealed around the inside and outside of the window frames, around sills and skirting using Tec7. Company who completed the thermal imaging recommended it. Tightened windows and replaced seals.

Not sure about the difference in the cooling of the house when it's windy to be honest. Will keep this in mind over the coming days and weeks.

The cold side of the house doesn't have the prevailing wind hitting it but does not get direct sunlight during the day. The other two rooms on the same side are colder compared to the rest of the house but they'll heat up quickly. The problem bedroom barely heats at all (radiator is a good temperature but is old).

Interesting to hear your thoughts on the issue. My knowledge is limited so great to have some theroies if I get someone out to have a look.

Could fitting insulated plasterboard have a positive effect in your opinion? Understand it's hard to say for definite without seeing the room in person.

MicktheMan

Was the house pressure tested (air tightness tested)?

If significant air leakage is the cause then this should be dealt with first and adding insulated pb isn't a good solution.

whizbang

Pic 1 - are those warm spots high up vents? - dont see them from inside.

Gable end wall seems to have very little insulation. Theres a significan stripe of heat along the bottom of the walls - thats probably under the dpc where insulation didnt go, compounded by the floors not insulated. Although the loss seems bigger under the windows- may be caused by higher air flow behind dot and dab plaster, and reduced cavity insulation also.

Internally you can see huge loss at top of walls. The dot and dab has to be replaced by insulated plasterboard. (sealed tight to blockwork with foam) Theres probably just a timber wallplate behind there, open to the attic and to outside.

whizbang

Treat dot and dab plaster as just a visual effect.. imagine no plasterboard at all, you will get a better idea whats going on. for instance the ceiling plasterboard will have a gap of about 1/2" all around the edges from the blockwork, up into whats basically outside air. If there was no plaster on the walls you would see this; you could blow smoke through the gap and wouldnt see it again.

Sealing skirting boards is great short term advice; but proves where the heat is going..!