I’m getting a stack of work done on my house…part of which is to be plastering over the artex ceiling in my kitchen.
The roof above is flat and there is no insulation (1920’s flat in Edinburgh). I am now thinking of just pulling the plasterboard down and insulating it then fitting plasterboard which should be way easier to plaster.
Given it’ll be the most heated room in the flat, it’s got to make a significant difference to heating & bills yes???Posted 9 years agowwaswasSubscriber
what fs said but you may not even need the studs – you can get 15mm insulation panels that really make a difference so those plus another layer of 15mm plasterboard and longer screws through to the existing ceiling joists and you’ll be fine and you’ve only dropped the ceiling 30mm.
If you do choose to insulate make sure you leave an air gap between the insulation panels and the underside of the roof and that there’s sufficient ventilation for the resulting voids.Posted 9 years agoStonerSubscriber
Ive used polystyrene backed pplasterboard on some of the internal outside walls of my house. Its ot 10-155mm plasterboard backed by 20mm-30mm of polystyrene. Easy to fix using dabs of bonding adhesive.
As Mike has suggested with 50mm PUR and 12.5mm plasterboard you’ll reduce the wall U value from around 2.1 to 0.4W/m2K or so.
That’s giving you an 80% saving through the walls which is tremendous. On your property though I’d imagine that if using a rigid foam thermal board you’ll need to use timber battens so the total build up will be in the region of 85mm.
Alternatively Aerogel will give you a few thin choices, the first would be a 2 layers of 10mm option ready bonded to plasterboard or Fermacell, this would take the U value to around 0.52W/m2K thus giving a saving of 75%. Both solutions can be fixed directly to the wall. Applied thickness is then 30mm.
A utility company is supporting the Fermacell option with funding through the CERT scheme so that could be very cost effective.
Another solution is to use a single layer of 10mm Aerogel with wet plaster, that would give a U value of 0.8W/m2K and a saving therefore of 60%.Posted 9 years ago
If I were you Al, I would stick in as much as you can – pull the old ceiling down, leave an air gap under (I assume sarking board in the ‘burgh)of about 40mm, then a soft batt of rockwool, then as said above a foam insulated plasterboard or aerogel right across the whole lot.
I would not batten it out as first suggested – you end up loosing a lot of the effectiveness of your insulation by cold bridges through the timber.
Insulation is (relatively) cheap at present, especially compared to increasing energy costs.
And yes it will make a huuuuge difference.Posted 9 years ago
Thanks all – I don’t mind ripping the ceiling down as the room is bare (no flooring, units etc) so the mess is fine, and would save me lowering the ceiling/creating a new framework of 3×2.
There’s a 1′ void to the roof (which is adjacent to and “breathes into” a pitch roof/attic space) so I’d thought I could fire up proper loft insulation into that then just fire plasterboard on existing battens – gotta be better insulation than 30mm of polystyrene etc (which can’t be a great fire risk for insurance purposes?).
Thing is I should really do the same to the other 2 rooms under the flat roof – I’ve just had the ceiling papered in the larger of them…Posted 9 years agoChalkyslideMember
I’d recommend getting some local expert advice on the matter – last thing you want is to form a “cold” roof with inadequate ventilation which could lead to condensation and rot to the roof construction over time. Most modern flat roofs are “warm” roofs (i.e insulation laid over the top of the joists) to help avoid a dewpoint within the structural depth of the roof.
For some independant advice maybe try googling TRADA and give them a call.Posted 9 years agospooky_b329Member
I ripped down my uninsulated kitchen sealing…replaced the plaster and lathe with 2″ polystyrene and plasterboard with an air gap to the tiles, can’t believe the difference after the recent snow…the first half is the insulated kitchen, second half is uninsulated bathroom.Posted 9 years ago
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