Garage (with room above) insulation

[Northy]

Hi guys,

Our garage is built into our house with our little girls bedroom above it. Basically we've always thought her room was colder than the other bedrooms so this morning I investigated a bit.

I could only see down the holes where the radiator pipes come up but there seems to be little or no insulation between the garage ceiling and the bedroom floor! :mad:

I'm gonna have to fix this but probably not until the weather is a bit better, but what's best to use? I've seen that spray foam stuff used on TV, would that be the best? I'm looking to seal and insulate.

There is also a mini roof bit that sticks out above the front of the garage (~4 foot), I'm guessing this area isn't well insulated either.

Is the easiest thing to take the ceiling down in the garage and work upwards?

Cheers,

G

[MatJohnson]

Why not get some of the space blanket insulation and stick it to the garage roof?

Sounds like a 2 person job, but insulation is generally on offer (2 for 1 the like)

[racingdwarf]

I thought a garage had to meet fire regs/building regs for fumes etc if built as part house, bit bad to have holes from garage to house:eh?: or is it sealed but with no insulation.

Anyway, thought you bred them hard up north? bit of cold should be fine:)

[bodgit]

I have same problem in my house. The bedroom above the garage is freezing compared to the rest with no insulation between the bedroom floor and cieling. I,ve thought about blowing polystyreen balls into the space from the garage cieling or outside walls or putting a false cieling in the garage with insulation blocks inbetween. Havent costed anything yet though.

[DCM]

If your going to insulate it, might as well seal it as well, fumes from the car can pass up into the bedroom otherwise.

[Ross]

I take it the ceiling in the garage is plastered ?, it should be double tacked for fire and building Regs. I would say it's easier to take this down rather than pull up all the carpet/flooring in your daughters room ?.

Depending on what room is between the floor boards and garage ceiling will dictate what can be fitted in the space. You should be able to 100mm celotex in there or 150mm wool insulation, both will make it warmer.

The ceiling will need to be double tacked again to bring back to Reg's.


I've seen on some of the DIY programs in the US the spray on foam, that look like fun to do :woot:. Not sure what that would cost to get someone todo ?.

I think makeing a false ceiling below the original will still give you a cold area between the floor and the new part ?

[snige]

Like Ross said it's easier to take down the slabs in the garage I wouldn't use the spray insulation as it can be a bit messy and if you have heating pipes in the roof space and get a leak on them it would be a nightmare to fix I'd use rock wool insulation it's used to insulate and sound proof buildings and then when re slabing the garage use a fire plaster board

[Col]

WE had a new garage built with a room on top 3 years ago. The lads put insulation in the floor, walls garage ceiling/bedroom floor and roof. They used some stuff I'd never seen before... it's like a big slab of foam covered with tinfoil! Even with that in every wall and floor it's still the coldest room in the house, but tbh I've always put that down the the fact it's 35ft x 12ft.

Also, I'd always take up the floorboards. It's got to be easier to work with gravity than against it!

[Ross]

They used some stuff I'd never seen before... it's like a big slab of foam covered with tinfoil!


That's Celotex.

[chris68nufc]

Depending on your budget you could put some heat mat down(underfloor heating) lovely touch to a cold bedroom aswell as putting cellotex on the garage ceiling. I have also used a foil layered sheet that you can also staple to the ceiling to help with heat loss.

[Northy]

Also, I'd always take up the floorboards. It's got to be easier to work with gravity than against it!

Thanks for the replys guys, very helpful.

What does double tacked mean?

How do I seal it? Moisture barrier? Whats all that mean then?

As for taking up the floor boards, it's a new(ish) build Col, about 10 years old or so? That means the floors are chip board and went down before the walls - a nightmare to take up!

G

[Ross]

Double tacked means two layers of plaster board, this is to conform with building regs.

Its for fire regulations, if you have two layers it will take longer for fire to get upstairs if it starts in the garage.

When its re-plastered, this will seal the room in good enough from smoke or draughts.

[cwp]

King span will do the job.
100 mm between the floor joist
25 mm going across the joist
Then 2 by 1 screwed to the joist to crate Air gap
Then re board with fire rated plaster board
And plenty off expanding foam to fill in any gaps.

[mattyts]

Underfloor heating FTW!!!!

[Mr_M]

Interesting to read this as the I've got a similar problem here - except that it's our bedroom above the garage. I don't mind it too much personally, but the wife doesn't like the cold!

In our case our garage has the boiler in it and hence also a frost stat which should keep the temp in there above 4 degC (to protect the boiler) but our room is still the coldest in the house. I did a quick check (drill bit through the garage ceiling in several places) and it seems as if in our case at least there is insulation in there already.

What i've done whch has helped slightly is to insulate the back of the garage door. Got one of these kits from B&Q (sort of foil sandwhich with insulating fibres in the middle) and taped it to the garage door as per instructions, (bit of extra draft-proofing on the edges too). Was a bit sceptical, but it was cheap enough so i thought i'd give it a go and it has made a difference - not huge, but noticeable. Has also made the garage much nicer for me to work in too!

Still looking for more improvements though - have also thought about putting another layer of insulation on the garage ceiling with another plasterboard skin on top - will probably try over the summer. Other than that, underfloor heating seems to be the only option - but it's a bit too £ for me and mega hassle (and if there isn't enough insulation below then you're just p*ssing away £ heating the garage).