Cold areas on recently built gable type extension

[GeddyMortgage]

We aways make sure that the eaves insulation detail, transitions to the roof insulation, robustly....

trap1.jpg

• noseall
• 11 Nov 2024

trap2.jpg

• noseall
• 11 Nov 2024

As said, external leaf masonry, ceases at the soffit.

Thanks @noseall looks as i'd expected, and nice and tidy. I've dug out a bunch of photos I took during the building of this extension, hard to verify exactly where there is and isn't insulation and frustratingly can't say for sure if it's in the eaves, but given that other areas look to be at the right height, I'd hope so?

I'll attach them chronologically below anyway for everyone, I wonder if anyone with a more trained eye than me can see anything that would help point to an issue!.

 

[GeddyMortgage]

And the rest of the attachments below.

What do you think?

 

[23vc]

I’d say the heat loss is more a consequence of the large glazed areas, ie. that end wall, plus the big velux’s, (possibly) combined with under sized heating, than the odd spot of missing PIR…does it feel colder/draughty down the end by the doors?

Are the cold spots in your thermal camera image, just in that one spot, or more widespread?

 

[GeddyMortgage]

I’d say the heat loss is more a consequence of the large glazed areas, ie. that end wall, plus the big velux’s

I suspect you're right. Once i've eliminated the possibility of draughts and/orr other easy to fix things, i'm gonna tackle those, it's still possible to change the units to triple glazed, or acoustic ones or whatever. Which is absolutely an option on the table. As is secondary glazing and/or shutters for any of the windows that are in the reveals. Not bothered about cost at this point just want it mega cosy!

…does it feel colder/draughty down the end by the doors?

It doesn't feel draughty, but it can be colderdown that end, to be expected to a degree with such large surface area of glass as you suggested.

Are the cold spots in your thermal camera image, just in that one spot, or more widespread?

More widespread, generally the walls and ceilings are similar temp apart from the odd bit here and there (even on internall walls which I guess is a good sign?!).... anyway, Images below

Window reveal and, area beneath the door / beneath the coir matting are the most frequent purple offenders on the thermal cam. Looks particularly bad round the edges of the window frames??

and one of the high up angled windows we think hasn't had the k glass thermal film thing applied to it, as there's a 3 degree difference in temperature between the left and right angled window, as shown on the image below, that's in hand with the installer though. Hopefully easy for them to rectify.

Only other thing I can think of is, when they ran the gas feed and the flow and returns for the rads and fire etc, they ran them all from the subfloor from the main part of the property to this extension.

I'm wondering if they've left any open channels when they cored through from there into this room, essentially allowing for cold air to be coming in through the airbricks to subfloor then piping into the cavities behind the skirting boards in this room....As the skirts are coming out mega purple on the thermal camera too. Fortunately the sub floor is accessible so im gonna go down there friday and foam up any openings etc.

What do you think?

 

[23vc]

Sounds like you’re on the right track. Interesting about the right vs left glazed units.
Draughts blowing up via subfloor sounds feasible. Another potentially very easy fix, is check where all the window/door frame profiles meet the (plastered) reveal. If it hasn’t got a visible bead of flexible caulk, it’s likely it could have a very small gap and enough to have a draught. Dead easy to caulk it, and see if it improves things.

Camera seems pretty cool, what type is it?

 

[GeddyMortgage]

Sounds like you’re on the right track. Interesting about the right vs left glazed units.
Draughts blowing up via subfloor sounds feasible. Another potentially very easy fix, is check where all the window/door frame profiles meet the (plastered) reveal. If it hasn’t got a visible bead of flexible caulk, it’s likely it could have a very small gap and enough to have a draught. Dead easy to caulk it, and see if it improves things.

Camera seems pretty cool, what type is it?

We noticed the the right angled window had arfefacts on it a few months ago, on closer inspection it looked lik the film had been put on backwards. We complained they took the unit away and told us a new unit had been made, but given the temperature difference, I reckon they just stripped the film off and give us ours back. Thats what the thermal evidence suggests anyway ha.

Yeah we've been caulking gaps between reveals and window frames, i noticed the last couple mm of the reveals was very flexible and some had cracked away, so I broke all that out to find a good couple of mm of hollowness behind, filled with foam and some rockwool, then filled and recaulked. I've done that on one of the window reveals and not the other, it has made an improvement albeit slight.

Other thing I noticed that i thought was odd, was there's no gasket on the inside of the fixed windows were they meet the frame, only external. All the other older windows in my house have gaskets both sides. So wondering if that's another booboo they've made, or maybe by design?

Camera is a FLIR pro, they're an attachment for your smartphone, do them both for android and IOS, think I paid couple hundred quid, has been a god-send for stuff like this, or a nightmare if you have ocd like me

 

[noseall]

like this, or a nightmare if you have ocd like me

That's why I'd never have one. I'm bad enough when I get the laser level out.

 

[^woody^]

Thermographic images, like damp meter readings require proper interpretation. They can look dramatic and may appear to show extremes and defects, but in fact things may be normal and expected.

Differences between different components are common, and not necessarily defects. Differences with similar components are suspect, but the assessment requires other factors to be taken into account.

 

[^woody^]

The purple highlighted bit may need investigation.

What are the temperatures of the three areas in yellow? Does your device indicate the high/low spot temperatures as well as the centre point?
If it's more than a couple of degrees difference, then it may need looking at.

There are the cooler areas at the ceiling/wall junction and that larger bit towards the right too. That ties in with the eaves issues mentioned previously.

While its cold, take some images outside at night while the room is heated for a few hours, to see if there are any obvious hot spots.

 

[noseall]

The purple highlighted bit may need investigation.

Looks like the settee is fooling the camera as well as that dado and below, panelling.

 

[GeddyMortgage]

Thermographic images, like damp meter readings require proper interpretation. They can look dramatic and may appear to show extremes and defects, but in fact things may be normal and expected.

Differences between different components are common, and not necessarily defects. Differences with similar components are suspect, but the assessment requires other factors to be taken into account.

Fair and appreciate it’s all relative.

That said. So far it has helped me identify 3 issues (door compression air leaks, window reveal air leaks, and likely lack of film on that angled window)

So the process is atleast somewhat working.

 

[GeddyMortgage]

The purple highlighted bit may need investigation.

What are the temperatures of the three areas in yellow? Does your device indicate the high/low spot temperatures as well as the centre point?
If it's more than a couple of degrees difference, then it may need looking at.

There are the cooler areas at the ceiling/wall junction and that larger bit towards the right too. That ties in with the eaves issues mentioned previously.

While its cold, take some images outside at night while the room is heated for a few hours, to see if there are any obvious hot spots.

View attachment 368566

Good shouts thanks Woody, I’ll take a look on Friday/Saturday and report back.

I wonder if that section is due to the oak panelling. Perhaps that’s just a colder material than a painted wall.

 

[noseall]

I wonder if that section is due to the oak panelling.

Looks like the settee is fooling the camera as well as that dado and below, panelling.

 

[GeddyMortgage]

The purple highlighted bit may need investigation.

While its cold, take some images outside at night while the room is heated for a few hours, to see if there are any obvious hot spots.

thanks for the advice. Good shout this. I got round to taking some images from outside today, its freezing here (-5!) and the heating ( just the radiators radiators, not fire) had been on for 3hrs or so when I took these.

One of the first things I noticed was all the windows looked a fairly consistent gradient. Barring the angled one which I suspected a problem with on the inside. On the exterior that one was warmer than the others. by 3 degrees or so. It's consistently 3 degrees colder than it's counterpart on the inside. So that confims its definitely a problem with those angled units? in that they're colder inside and letting more heat pass through them than all the others. I still assume thats due to them not having the K glass reflective thermal film stuff, but i'll sort that.




Anyway, on the other side of the roof, I noticed something interesting. The chimney for the balanced flue fire I have in that room was lighting up much warmer than everything else.

What is perculiar about that is that fire hasn't been on for a good few days. So left me a bit puzzled as to why heat would be essentially escaping from my room up there when my fire is a balanced flue type meaning all the flue is sealed to the chamber of the fire etc. The only heat generated in these photos is the warm air from the two radiators in that room.

Then i remembered installer of the fire did put in some vents in the faux chimney breast to help dissipate heat from away from it when the fire is on and allows said heat into the room etc. Itook a photo of those, sure enough looks like warm air was going in there. (again i'll mention to be super clear the fire is not on here and hasn't been for a few days)

So started to wonder if perhaps the warm air is going in those vents then maybe escaping somewhere up through the roof at a location hidden within the breast, likely where the installer had go take the flue through the roof and maybe left it not perfectly airtight?

Trying to confirm that, I left it a few hrs for the room to cool down and took some photos again to see if the chimney bit would stop showing the heat signature from previous, essentially I guess that would mean whatever warm air was in there, has now gone away since the heating has gone off leaving, the chimney to be the same temp as the cold roof tiles etc.... And Interestingly that is what i observed.

That has led me to believe there likely is some sort of air leak coming from there, letting cold external air down into the breast, then out the vents and into the room. So will investigate that tomorrow morning with some more photos.