Cold cold room!

[caslin]

I`ve just bought a house with a bedroom above the garage. Looking up at the room from the garage i can see the floorboards of the room above.

There is plasterboard attached to the rafters with a few holes in and by the looks of it not much insulation.

The room above is cold as you would expect. Above the room in the attic appears to be some kind of space blanket insulation.

My question is what is the best insulation to place inbetween the rafters above the garage/under bedroom floor?

Ive looked at insulation ranging from fibreglass to celotex rigid boards. I now give up.

The joists are 6 inches.

Any help/advice greatly appreciated.

 

[^woody^]

Foil backed boards are roughly twice as efficient as quilt for any given thickness.

However, quilt may be easier to install

The garage will need to be double boarded, with lapped and sealed joints too, for fire and smoke protection

 

[caslin]

What thickness of board am i looking at if im double boarding the garage aswell.

6 inch joists but do i need 150mm boards?

 

[DIYedboy]

Remember that you only lose 10% of heat through the floor, so you don't want to spend a fortune on that. If your bedroom has outside walls they will be the major heat loss (30%) especially if they are solid and face North. If they do, bung 6" of quilt under the floorboards (cheap), double board the garage ceiling and fit 60mm thermal plasterboard on the walls (£40+ a sheet). Then it's into the loft to put 8" of quilt on the ceiling

 

[kbdiy]

Make it 11" or more on the ceiling. That's the current standard and it's cheap as chips.

 

[caslin]

Thanks for the advice.

 

[caslin]

Thanks for the advice.