Loft insulation

30 Nov 2007
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United Kingdom
I wish to install loft insulation to the equivalent of 270 mm glass fibre blanket. I also want to put down flooring in the loft.
However, my joists are only 100 mm deep so I cannot put down a floor and glass fibre blanket to a depth of 270mm.
Is there an alternative insulation material which is no more than 100 mm thick and could give me the required level of insulation ?

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100mm Joists are not the best things to be flooring over anyway.... far to flimsy for anything other than very VERY light storage.

Is the roof structure made from Prefab trusses by any chance?

If you must do this, then insulate to 100mm, then floor over that....
for the extra insualtion install somethin glike the Eco Alu bubble foil across the eaves.... works better than you think it would...

If your adamant you want the total amount of insualtion between the joists, then fit new batterns a right angles to the joists, thus allowing space for insulation, then floor onto batterns..... but this way adds much weight to your already not so big joists..
Just contradicted yourself there MA.

I agree with your previous comment, he should crossbatten with 2x2 before insulating, to help spread the loading.

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