Extension (Roof) Insulation & Downlights

[HomerOwner]

My question pertains to ceiling insulation within Pitched & Flat Roof extensions, and downlights.

I bought an 80s house with a side extension (added ~8 years ago). The extension roof covers a dressing room (pitched roof, tiled) and en-suite bathroom (flat roof, fibreglass). Unfortunately didn't get any documents from the previous owners so I'm light on details regarding the construction. They seemed to think the planning/building regs sign-off was everything and that's all we got provided.

The dressing room has downlights (adjustable) that let terrible draughts through during winter storms.
The en-suite bathroom has proper IP-rated downlights (with gaskets) so no draughts, but it is BLOODY COLD in the winter (11c max).
I believe both are "Cold-roof" style (due to neighbour challenges to the height during planning).

I stuck a boroscope up through the downlights to have a peek and take some pics. I'll add the second set of pics in the next post.

Extension 1, Dressing Room roof (pitched, tiled):
- It looks like this doesn't have much insulation, if any? Besides a thin layer of (foil backed?) foam(?) immediately against the ceiling, that the downlights attach through.
- The rest seems to be a void all the way through.
- The upper layer looks to be some sort of breathable membrane(?), then presumably the tiles above that.

Doesn't this need any sort of insulation at all up here? I know one needs to be mindful about moisture & leaving a void, but I'm concerned about heat loss, and the downlights have obviously breached what is there.

I'm planning on replacing all the downlights with fixed (non-adjustable) ones, (fire & insulation contact resistance rated, of course), that should at least help a bit. I need GU10 ones as we use smart bulbs, rather than the integrated LED type.
To prevent draughts, would that do, or do I need IP bathroom style ones (here in the dressing room), too? (As I know these have gaskets).

We'll be having some roofing work done soon, so presumably they'd be able to get at this from the top side, by removing the tiles / membrane, if needed.

 

[HomerOwner]

Extension 2: En-Suite Bathroom Roof (Flat, Fibreglass):
-This one seems to have the same (foil backed?) layer, breached by the downlights, of course.... IP-rated, at least so no draughts.
- This also seems to have a thick layer of (foam, Celotex?) insulation blocks, with square sections missing where the downlights are.
- There is then (presumably correct) void between this layer and the boards above, under the flat roof.
- The flat roof installers had installed a couple of "soffit" style vents at the end, presumably to allow for airflow to that section.

As this section DOES look like it has installation blocks, does it need any more?
What about those missing sections where the downlights are? (You can see this in pic 3).

Again, I'll replace these downlights too with proper fire-rated & insulation contact resistance ones (IP65-rated, of course), but again I'm wondering about cold spots, where those have breached through.

As the flat roof is apparently fairly new, I won't want to replace this. However I will be renovating the bathroom in future so doing something from the inside, would be possible.
Unfortunately won't be able to change it to a "Warm roof" style, due to height restrictions mandated in the planning (Neighbours..).

 

[jj4091]

Not sure about your insulation/ventilation concerns but if you are bothered by draughts have you considered replacing the downlights with modern led flush fittings.

 

[HomerOwner]

Not sure about your insulation/ventilation concerns but if you are bothered by draughts have you considered replacing the downlights with modern led flush fittings.

Yep. I can't use the standard LED type as I need GU10s since I have smart bulbs.
As mentioned I'm planning on replacing all the downlights with fixed (non-adjustable) types, (maybe even full IP-rated bathroom ones with the gaskets). Fire rated & insulation contact resistant. I'm hoping this will resolve the draughts.

There's the still the matter of (no?) insulation for Extension 1, and huge squares being chopped out of Extension 2, though. (Actually the same side extension but different parts). Both areas are bloody cold!

I'd love to get an infrared camera and look, but I just know it's going to be dark blue lol.

I hope the ONLY resolution isn't:

1. Get a time machine.
2. Go back to before the point where you decided to install unsuitable lights or buy a property with them installed.
3. Persuade yourself to change your mind.

 

[jj4091]

Yep. I can't use the standard LED type as I need GU10s since I have smart bulbs.

You could just swop the switch for a smart one

 

[HomerOwner]

You could just swop the switch for a smart one

Nah these are Phillips Hue LED GU10s. Used for nightlight scenes etc. Nothing to do with switches.

Regardless the GU10s aren't the problem, how the downlights were installed, is.
Unfortunately when buying a house you don't get to be poking things up through the downlights until afterwards! I really would like that time machine..

 

[Deluks]

They seemed to think the planning/building regs sign-off was everything and that's all we got provided.

Was it signed off by a Mr Steven Wonder?

Is there any indication of insulation between that OSB deck and the fibreglass roof deck?

It looks like insulated plasterboard has been used, this would normally be in addition to a much thicker insulation layer above it, it's woefully inadequate by itself.

 

[Murdochcat]

Nobody in their right mind should fit sealed LED downlighting

IIRC KSR do adjustable GU10 IP down lights

 

[HomerOwner]

Was it signed off by a Mr Steven Wonder?

It seems so! They apparently had some sort of private inspector / adviser during the building works, too. But everything I'm finding that those builders did seems to be wrong, so they can't have done a good job and I've no idea how they got it all certified less than a decade ago.

I know the "proper" solution would be to rip them all out, seal up and put in a proper light fitting blabla, but that isn't feasible right now, unfortunately.

Is there any indication of insulation between that OSB deck and the fibreglass roof deck?

It looks like insulated plasterboard has been used, this would normally be in addition to a much thicker insulation layer above it, it's woefully inadequate by itself.

All I know is what I can see in those pics with my boroscope. The fibreglass roof was newer (replacing the original bodged one) and was done by a different, reputable company at least. All I know is it's the "cold roof" style due to there being height stipulations from the neighbours. (Sun angle is at x degrees at xx:yy:zz.0000 and any higher would cut off light to their extension blabla".

That en-suite bathroom has a thicker layer on the plasterboard, then those large "bricks" (celotex?) you can see in the pics. Of course with huge squares cut out for the downlights! (Seems to be a common stupid thing builders do, and for people to get them installed in the first place. Everything seems to have been done for aesthetics).


The dressing room section has a pitched roof above, with tiles. But then NO insulation at all besides the thin layer on the plasterboard?

Nobody in their right mind should fit sealed LED downlighting

IIRC KSR do adjustable GU10 IP down lights

Why not? And hm I thought all IP65s weren't adjustable. We don't have a problem with light direction, at least so straight down is fine.

As to the dressing room they don't HAVE to be sealed, but that's the problem. The current lot, (being adjustable) let huge draughts through around the adjustable bulb bit. When it's stormy it's like having the window open!

 

[Murdochcat]

https://www.tlc-direct.co.uk/Technical/DataSheets/KSR/FireBreak_QR_Datasheet.pdf

 

[Deluks]

I've no idea how they got it all certified less than a decade ago.

It's not just builders who are chancers these days, some professionals can be very unprofessional...

Everything seems to have been done for aesthetics).

Happy wife happy life!

All I know is it's the "cold roof" style due to there being height stipulations from the neighbours. (Sun angle is at x degrees at xx:yy:zz.0000 and any higher would cut off light to their extension blabla".

I think the neighbour would've put me off buying the property before the dodgy insulation job did.

When it's stormy it's like having the window open!

You might as well go and live in the garden!

I can think of mamy other unhelpful snarky comments, but ultimately what needs doing is the ceiling or roof taking off, and a proper amount of insulation fitting, with care taken to ensure no cold bridging, vapour barriers etc
Watch the Steve Roofer channel on YouTube, he's brilliant at explaining things.

All this talk of downlights is derailing the conversation, get the roof properly sorted and you have whatever lights you want.

 

[HomerOwner]

You might as well go and live in the garden!

I can think of mamy other unhelpful snarky comments, but ultimately what needs doing is the ceiling or roof taking off, and a proper amount of insulation fitting, with care taken to ensure no cold bridging, vapour barriers etc
Watch the Steve Roofer channel on YouTube, he's brilliant at explaining things.

All this talk of downlights is derailing the conversation, get the roof properly sorted and you have whatever lights you want.

Thanks, indeed it's like being outside!

I personally dislike downlights (though my wife likes them, too. Women...) and if we do a major redecorating job one day in future, I'd probably have the ceiling down and get the holes filled in, insulation replaced and have some proper, normal lights. However after recently buying the house, new carpets and an upcoming roof refelt, that won't be financially feasible for a while!

So in the short term I'm hoping to just replace all these stupid downlights (13 in the kitchen, 6 in the dressing room & 6 in the en-suite) with proper fire rated, insulation contact resistant ones, so I at least know what's there (as everything they had put in seems to be cheapo or wrong), then hope to address the draught / insulation issue.

The reason I didn't trust the adjustable ones was because the current ones are, and that's where the draught comes from. The fixed, bathroom ones don't have the draught as the bezel isn't recessed, and has a gasket.

I'm researching every damn topic & youtube vid and not really seeing a good solution for an existing install, besides getting the fixed ones (or the ones Murdochcat linked), or fitting loft lids over the ones that roofers could get to from above (dressing room), sealing them, and then banging rockwool or something over them? (Being careful to leave a gap above for airflow).


As to the rest of the dressing room, I'm presuming that needs some (celotex?) insulation up there?

Steve the Roofer's vids were helpful, however he stipulates using a dropped ceiling, which isn't feasible with our rooms, unfortunately. (The dressing room wardrobes would also need to be changed as they're up to the ceiling).
These things are absolutely stupid and purely for aesthetics, arrgh. It boggles my mind how builders just put up either no insulation, or chop out huge chunks of it, and then that somehow still gets signed off!

The En-suite is 11c and dressing room 13c in winter!

 

[HomerOwner]

Right, we have a plan.
I was comparing the JCC Fireguard and KSR Firebreak GU10 lights, they seem to be pretty much equivalent? (Besides the KSR FB requiring 100mm to the JCC FG's 150mm). The missus actually likes the bezels on those better, too. Cheers @Murdochcat.

- Replace all bathroom downlights with KSR Firebreak QR Fixed IP65.

- Replace all non-bathroom downlights with KSR Firebreak QR Tilt. These seem to be fully canned with no gaps(?) so should stop the draught even though they're adjustable.

- Have roofers add rockwool insulation over the dressing room & kitchen extension lights, and anywhere else (from above. We're having the main house tiles off for a re-felt soon anyway, so they can nip under the extension tiles too and add some insulation, while they're at it).

- Whenever we re-do the en-suite one day, have the ceiling down, and put it back up with insulation over the downlights. (Shame we didn't know about this before the flat roof was done. I suspect they didn't expect to see the missing insulation either, and it will have been too late once the roof was already off).

- Use CFix Repair kits to reduce the size of the gargantuan holes in the bathrooms, to the 70mm for the firebreaks: https://c-fix-downlighter.com/pages/c-fix-repair

- Add CFix liners to all other downlights to prevent the plaster/insulation from being further destroyed: https://c-fix-downlighter.com/pages/c-fix-liner

Hopefully, that will even please @ban-all-sheds (as these apparently satisfy Part B, C, E), and get around this whole problem without needing the time machine.

 

[robinbanks]

Have you considered blowing loose-fill insulation in?

 

[HomerOwner]

Have you considered blowing loose-fill insulation in?

Hm got a link for exactly what you mean by that one? Seems to apply to a variety.

Also will that work without "filling" it too much up there?
The KSR Firebreak QR Downlights state: "The downlight can be covered in mineral wool insulation, however where possible allow an area around the fitting for ventilation". Apparently the depth to support is 100mm and it's not to be "draped over", rather than "packed in" to the sides of the can.

The pic attached is from JCC's illustration of what that means (rather than KSR), but the principle is the same.