insulating concrete garage and extension roof

[Teajunkie]

Ok this may be a bit of a non starter due to costs but im looking into insulating my workshop and laundry room.

currently on the side of our bungalow we have a single skin extension with garage i will add pictures later.....
it has a corrugated asbestos roof which gets wet and mouldy in the winter, now this wouldn't normally be an issue as we have a dehumidifier running 24/7.
Now the wife has stock out there its not good enough and we need a more permanent solution.

can i just nail some hardboard to the beams and stuff the gap between with loft insulation?
and im thinking batten the walls and do the same with them to insulate them.

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For some reason the pictures have uploaded upside down?
but you can see the mold on the roof in the garage and laundry room and even the water on the roof in the toilet!
Although the garage isnt wet on the roof the walls are very cold and damp. I have already coated the walls with some paint on sealer that looked like concrete which helped keep the mold out from the walls.

[BigBird]

I would then use some 25mm thick foil lined insulation boards. Seal any gaps between the insulation boards with expanding foam before finally cladding the walls and ceiling with 1/4 ply. I bought some insulation boards recently. 4' x 8' foil lined insulation boards shouldn't cost more than £11 + vat each. (">

[hoponbaby]

Got 2 sheets of 50mm celotex left over here you could have used between the joists but a bit far to collect

[Teajunkie]

Got 2 sheets of 50mm celotex left over here you could have used between the joists but a bit far to collect

Yeah just a bit thanks for the offer though fella.

[Teajunkie]

I would then use some 25mm thick foil lined insulation boards. Seal any gaps between the insulation boards with expanding foam before finally cladding the walls and ceiling with 1/4 ply. I bought some insulation boards recently. 4' x 8' foil lined insulation boards shouldn't cost more than £11 + vat each. (">

is this the stuff you mean?
http://www.wickes.co.uk/Celotex-25mm...400mm/p/190545

[hoponbaby]

That's the stuff but I'd use the thickest that fit between the joists. You need to leave an air gap between the sheet and the underside of the existing roof though.

Don't but it from wickes/b&q etc though, should be able to get it for £10-15 a sheet depending on thickness

[BigBird]

is this the stuff you mean?
http://www.wickes.co.uk/Celotex-25mm...400mm/p/190545

Yes that type of board. The ones I got were QuinnTherm but they are all pretty much the same. One local builders yard near me sell them for £11 + vat. When they didn't have any in stock I managed to knock the price down at another builders yard from £14 +vat to £11 +vat. (">

http://www.insulation4less.co.uk/ins...uinntherm.html

[akimba]

Also put a waterproof membrane against the wall before you put in the Celotex this will stop the damp coming thru but allow the walls to breathe.

[Teajunkie]

As i first thought its getting quite expensive already, so off to local builders yard to get some prices and i may even get a few quotes from local builders.

[akimba]

I did it not long ago and turned me old washouse into a pool room biggest expense for me was the cellotex which I bought off ebay in the end.

but a plasterer owed me a favour so he boarded it out for free but still waiting on him comin back and skimming it out tho, that the problem wi favours :-(

[Squizza]

I did my cellar.
I would put some 30-50mm celotex, then add some foil backed plaster board as mentioned.
Definitely add a damp proof membrane to the floor. This could be the paint on stuff or a sheet.

The key is to provide ventilation otherwise you will get mould.