The lounge in our new place was extended c30 years ago, and the extended bit is probably a third of the total area. Over the extended bit is a small slanted roof off the front wall off the house. There’s no access into this roof space so I can’t see if there’s any insulation up there, but even if there is its going to be 30-odd years old… The room can be cold, and having a third of it uninsulated probably isn’t helping.

Currently there is a beautiful artex ceiling on that portion, which we will be getting rid of at some point. I had a thought that, whilst that’s being done, we could take the opportunity to replace the ceiling with some insulated boards or something similar? Does such a thing exist?

Kingspan, Celotex, etc are asy to use.
Also insulation backed plasterboard works very well.

our kitchen in our present (10 year old) house had a single story bit with a slanted roof with no internal access. FA insulation up there.
We had to have some of the roof taken off to get the insulation in there.

remove a few boards, insulate with rockwool and then replaster

I’m doing this right now. My dining room is a lean to extension but it’s notably cooler than the main rooms. There’s enough space to sit/crawl, but no hatch in the ceiling. I’ve put a hatch in and am replacing the insulation up there that is a bit on the thin side and has been ruined by mice living in it. Fortunately, the mice are long gone, but it’s taking a while to clear out the old glass fibre in a small space.

taking a while to clear out the old glass fibre in a small space.

Vile job that, I had to do our whole loft as there was no charge for insulated lofts but a few hundred quid for a top-up on whatever scheme paid for it at the time. Was itching for days after, and it’s bloody messy too.

Just put new over the old stuff. Compact it a bit if really necessary, the ‘pros’ just roll it out over joists anyway.

Our hallway is the same – no access and very little insulation.
We’ll be having a bit of work done on it in the spring that will include lining paper removal and skimming, so we’ll probably cut a big hole, install insulation (not decided which yet) overboard and skim.
PITA though.

One thing to consider is ventilation for the resulting uninsulated roof void.

You need to make sure you don’t end up with a big cold and unventilated space above the now insulated ceiling where moist air can get in as that encourages condensation and, in the end, rot.

We have the same, an overhanging roof which make up part of our lounge ceiling. Doubt there is any insulation it the space at all. Shame really as Access is bloody tight without an access hole. Still thinking up methods I could use to get insulation into the hole.

Having done it a few times I wouldn’t bother messing around nowadays especially with a hideous textured ceiling. Pull it all down, sort out the electrics, fit 100mm Kingspan between the joists then re-board and skim. It really isn’t a big deal and it will be easier than messing around trying to get access to the space then fitting insulation from above.

This was what we had to deal with when we bought our present house; pink gloss Artex! Bleargh… puke…

Simplest and cleanest method:-
38 x 25mm battens screwed through the existing ceiling, 62.5mm K18 insulated plasterboard fixed to battens, tape and fill joints, emulsion, job done…you may want to assess the impact this will have on your existing ceiling height!

Messy ballache of a method:-
Strip existing ceiling lining, insulate in between joists, 12.5mm plasterboard, tape and fill joints, emulsion, job done.

Pull it all down

If its lathe and plaster, that is one hell of a messy job!

Christ, i just don’t think the other half would be happy about that. Wish we had done it when we decorated. Alas that’s not an option.

You need to make sure you don’t end up with a big cold and unventilated space above the now insulated ceiling where moist air can get in as that encourages condensation and, in the end, rot.

What, like that big space above our insulated ceilings, usually known as the loft? Or is a roof ventilated? 😕

Or is a roof ventilated?

yep.

The loft area (should) be ventilated if done correctly. lots aren’t.

I second the batten out and kingspan then overboard method, assuming you have sufficient ceiling height, it has much better insulation properties than rock wool.

We had 2.6m ceiling height so ours got 100mm kingpan and then a thermal board over the top. went from a horrible room that no one went in, to the warmest room in the house.

You can try pointing and jibes about its mother. But most ceilings are pretty thick skinned.

Ill bet you haven’t done the dog flap yet (one job at a time.) 😉

As it’s only a ground floor extension wouldn’t it be easier to gain access by lifting few tiles, and pulling back the membrane?

If roof is lean-to with flat ceiling, remove a section of tiles, cut a hatch between rafters in felt and cut section of batten out. Climb inside, mineral wool insulation between joists, then cross layered over the top of joists, aim for 300mm total minimum. Make good felt, replace section

If roof is lean-to with flat ceiling, remove a section of tiles, cut a hatch between rafters in felt and cut section of batten out. Climb inside, mineral wool insulation between joists, then cross layered over the top of joists, aim for 300mm total minimum. Make good felt, replace battens, re-tile, job done.

If sloping ceiling inside, I’d either rip down ceiling, Celotex between rafters (leaving 50mm air gap to felt), then overboard in 25 or 50mm Celotex, then PB and skim. Or. Leave ceiling in place, overboard with 25 or 50 Celotex, then PB and skim.

Don’t ignore the ventilation (or do a good job fitting vapour barrier if you don’t ventilate).

We had an asbestos board inner roof lining removed in our garage. The poorly ventilated joists and roof deck above were rather wet – I initially thought we had a leak but many weeks of wet weather and dry joists would suggest it was all condensation.

I’m currently insulating and re-boarding with much improved ventilation front / rear to draw air through above the insulation.

If it’s 30 years old, there’s a fair chance the Artex has asbestos in it. Take care!

If it’s a third of the room, battening and board will cause uneven ceiling height.
Abouut to do this in a loft room – going to batten and screw celotex board over the old lathe and plaster, rather than the mess of removing it.

We did something similar to this.

Pulled the insulation through.

Got that stuff that comes in the silver rods all sealed up.

Cut an opening at one end of the ceiling and another at the other end. Put a cable though and pulled the funds of insulation through carefully. It worked.

Replaced the bits we cut badly. Framed the roof of. Put in 2inch insulation board and the finished with those slot together ceilings.

Looked OK. Totally changed the bathroom extension