reinsulating my internal garage

[mikeF00]

Hi, i have an internal garage which I believe is causing the adjacent internal rooms in the house to be cold. There is no plasterwork of any kind on the inside walls of the garage(just bare breeze block) and although there is some loose wool looking stuff in the cavity between the roof joists(beneath floor of bedroom) , it doesn't look great. Also,the plasterboard on the garage ceiling looks normal plasterboard to me.

I want to improve the insulation , and quite fancy tackling this myself, but wasn't sure about regulations though ? Anybody know about these, or where I can find them?

 

[wickedwjc]

Hi Mike,

I'm no expert but if you're looking at improving the insulation on an existing property I don't think building regs apply - anything extra is seen as a bonus! You could try the planning portal online for more info.

I'd imagine your best bet is to swap out the wool (most likely spun fibreglass?) insulation for PIR boards (Celotex, Kingspan etc..). Won't be cheap but will definitely make a difference to the adjacent rooms. If you want to go all out then you could also replace the plasterboard with the insulated boards to add an extra layer.

 

[mikeF00]

Thanks for replying.
So, I could fill the cavity between the current garage ceiling and bedroom floorboards with the solid insulation you mention? What about small gaps and nooks & crannies left over?
Any ideas ?

Also, what about the walls of the garage? I wasn't sure whether I should bother about wall that faces the outside?( if you know what I mean). But the other 2 walls I should consider right?

 

[wickedwjc]

You can cut the PIR boards to fit between the joists quite tightly, however if you really want to fill in all gaps you could use expanding foam (not entirely necessary but up to you)

For the walls I'd leave the external facing walls like you say, but for the internal ones maybe look into using insulated plasterboard like Gyproc Thermaline Plus (can be dot & dabbed directly to the wall).

 

[mikeF00]

Hi, I've seen somewhere that you have to take into account some kind of air gap for ventilation? Do you know what situation calls for this? It might not apply in my situation.

 

[Nozzle]

If you take out soft insulation and replace it with rigid insulation you may well find that it's just as warm but noise transmitters better through the rigid stuff than the soft stuff

Nozzle