Loft Installation question re laying over boards

1jim

Hi
Does anyone know if the professional loft insulators will lay loft insulation over a partly boarded loft?

My loft is approx 1/3 boarded, I had planned to buy the insulation and lay properly where possible and then lay some over the boarding (I dont know if that will work insulation wise but my thinking was that it has to be better than northing??) but when costing it out it seemed cheaper to get someone else to lay it for me but if they are going to come and survey and tell me to take all boards up etc then its not worth wasting their or my time
any advice welcome on if this is ok to do and if they will do it
thanks
jim

fluffymuffy

It's not a good idea to board a loft.

If you put boards over the insulation it squashes it down to a level where it's not very effective as an insulant. The insulation works on the principle of storing so many inches of air.

A boarded loft gives the impression that it's a load bearing floor - which it isn't. Your ceiling joists were sized to take the weight of the plasterboad and perhaps a bloke with a torch above once in a while to inspect the roof space.

Lofts, especially those insulated from the rest of the house, are very poor spaces to store things.

Sorry - this isn't a very helpful post - I just like to moan about loft boarding .

latecomer

Of course if the insulation under the boards is just to the top of the beams then it will work as intended while still allowing you to have a floored area.

1jim

the trouble is the loft is already 1/3 boarded, only used to store suitcases etc and is used to access the boiler. Dont really want to have to go to the trouble of taking it all up and relaying it over the insulation. Just really need to know if having insulation on top of the boards has any benefit at all really and if it has will the people who do the grant schemes lay it over boards
thanks
Jim

lilac_lady

I had a partially floored loft and the insulation installers covered it all except an access path to the water tank. The didn't lift the boards up. Hope this helps.

1jim

thats great thanks, it will work out a fair bit cheaper to get them to do it for me than buying it myself which is odd really but I guess theres no way accounting for government/business sense
jim

Angela

I am a loft (and cavity) insulation surveyor and my company will not lay over boarding.
All boarding must be taken up,and just a 1/2 metre (wide) walkway must be made so if anyone has to work on your cold water tanks or boiler they can see where to tread.
The insulation will not be effective if placed over boards.
Again you must not board over insulation as this will compact it and causes condensation and more problems.

HTH

fluffymuffy

Angela wrote: »

The insulation will not be effective if placed over boards.

Whyever not?

wallbash

Mate has just moved into a new build, masses of wonderful insulation

But have spent time bagging lots of it up !!!
House is very small , but for the cost of a few pounds he can have all the storage space he wants. Still has 'some' insulation , between rafters.

Yes his heating bills :eek: will be higher, but far lower than the storage he was paying for.

Life is always a compromise.

wildmandy

Angela wrote: »

The insulation will not be effective if placed over boards.
Again you must not board over insulation as this will compact it and causes condensation and more problems.

HTH

That's nonsense! Insulation WILL work over boards.
Insulating under boards is also very effective, seeing that normally 100mm thick rolls are used between the joists which are normally around 12-13cm high. Thus it won't be compacted.

Mandy

djohn2002uk

wildmandy wrote: »

That's nonsense! Insulation WILL work over boards.
Insulating under boards is also very effective, seeing that normally 100mm thick rolls are used between the joists which are normally around 12-13cm high. Thus it won't be compacted.
Mandy

Except that the recomended thickness was 270mm 10yrs ago. Must still be at least that now if not more.