Nearly Retired (I am now) Posted February 23, 2011 Share Posted February 23, 2011 Our ceiling / roof construction comprises the ceiling which is a layer of 20mm thick softwood T&G boards fixed to joists spanning across from the centre to both front and rear walls from a chunky ridge beam. Above the T&G, and spaced in between the joists are slabs of 50mm or so, thick expanded polystyrene. Above the polystyrene the void extends upwards from about 70mm at the outside walls to say 500mm at the ridge. Then we have the roof construction of 15mm thick cedar (?) boards on top of which are the canal tiles.Quite why the the ceiling does not follow the roof in parallel I don't know, but the void varies in thickness. It would be good to fill this void. What way might there be to fill it with insulation with the minimum of disruption and cost?I like the idea of pumping it with something like polystyrene balls or other "fluff", but I don't suppose an air gap could be properly maintained above the new layer and underside of roof - I think it all might slump down to the walls each side.Taking off the roof or removing the ceiling would obviously work but the cost would be huge and not worth it. Making a large hatch in the centre of the ceiling in each room on the first floor might give access but probably not enough. Then there would be the problem of disguising it later. Does the panel have any ideas please? Link to comment Share on other sites More sharing options...
ericd Posted February 23, 2011 Share Posted February 23, 2011 So if I understand correctly, your roof design has a shallow angle(Charentaise...) and the ceiling underneath is horizontal.....Above the ceiling you have the 50mm polystyrene then the void difference between that and the outer line of the roof. Why this design??? may be the last owner wanted to restrict the cubic area of the room in order to make it easier to heat....Now how can you add insulation to this pyramid looking void?I would actually add solid rockwool insulation slabs and build them in form of a pyramid. First slice across the whole floor, then a second slice over the now restricted floor area etc...Does this answer your question?? Link to comment Share on other sites More sharing options...
Nearly Retired (I am now) Posted February 23, 2011 Author Share Posted February 23, 2011 Does this answer your question?? Thanks, but no it doesn't"I would actually add solid rockwool insulation slabs and build them in form of a pyramid. First slice across the whole floor, then a second slice over the now restricted floor area etc..."Thanks again, fine in theory but how do I get in there to fit them. That is the question. The gap varies from around 500mm to 70mm.Unfortunately, I don't know any midgets I can rely on ! Link to comment Share on other sites More sharing options...
PaulT Posted February 24, 2011 Share Posted February 24, 2011 Personally, if it was me, my first aim would be to get the polystyrene slabs out and as for adding polystyrene balls eek!Only a very slight risk but the gases given off by polystyrene when alight frighten me.Paul Link to comment Share on other sites More sharing options...
Théière Posted February 24, 2011 Share Posted February 24, 2011 [quote user="PaulT"]Only a very slight risk but the gases given off by polystyrene when alight frighten me.Paul[/quote]The polystyrene produced these days doesn't burn in the same way as our old 70's ceiling tiles did (self extinguishes) so not sure what gasses are given off any info would be very useful.O/P sounds like you need to cut an access panel into the ceiling as you can add insulation but you also need to maintain air circulation which you probably knew. Link to comment Share on other sites More sharing options...
ericd Posted February 24, 2011 Share Posted February 24, 2011 Can also remove a few tiles, cut the planks to get access, fit insulation and re-tile. Afternoon's job. Link to comment Share on other sites More sharing options...
Nearly Retired (I am now) Posted February 24, 2011 Author Share Posted February 24, 2011 Thanks ericd, but the void is around 500mm only so you can't climb in.In reality, get scaffolding, remove all roof tiles from 150+m2 of roof and carefully lay to one side, remove all boarding and carefully lay to one side. Ensure it does not rain for 3 weeks. Cut and lay insulation. Re-fix boards allowing for 10% wastage of original ones. Re-lay canal tiles. Strike scaffolding and remove from site.After a long lunch, stand back and admire morning's work ! Link to comment Share on other sites More sharing options...
Théière Posted February 25, 2011 Share Posted February 25, 2011 [quote user="Nearly Retired"]Thanks ericd, but the void is around 500mm only so you can't climb in. [/quote]500 x ? it sounds big enough to sqeeze into based on working in the eves of standard lofts, never comfortable but do-able. Link to comment Share on other sites More sharing options...
Nearly Retired (I am now) Posted February 25, 2011 Author Share Posted February 25, 2011 Unfortunately that won't work. Maximum is 500mm ranging down to 70mm.Anyway, I'm not taking off the bloomin roof ! Link to comment Share on other sites More sharing options...
Théière Posted February 25, 2011 Share Posted February 25, 2011 What about from the inside, sorry that is what I meant Link to comment Share on other sites More sharing options...
Nearly Retired (I am now) Posted February 25, 2011 Author Share Posted February 25, 2011 Yes, if we are going to do it at all, it will be from the inside. Either we fix insulation to the ceiling surface where there's plenty of headroom or the more aesthetically pleasing solution (i.e. invisible - ish) above the ceiling.For access we would need to cut pretty large holes in the 20mm thick T&G, but with a bit of framing might make the final finish of the re-filled holes look original. A T&G ceiling with a couple of symmetrically placed 1m x 1m framed areas might look OK. I could do it on room by room basis and see how I get on.I will give that idea some thought Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.