Loft insulation issues

Jun 10, 2014 18 Replies

Greetings



I am planning to have my very ageing roof retiled. In the process I am going to insulate the loft. Currently there are boards on top of the ceiling joists, with insulation here and there underneath the boards. The loft is used to store a lot of stuff, access to which is via a foldaway loft ladder.



I picture putting mineral wool stuff up to the level of the joists, then rigid boards on top, followed by wooden boards to allow the stored stuff back in again.



BUT - for the loft ladder to work, the space that it folds onto would have to remain at its current level, i.e. atop of the joists, so not as fully insulated as the bulk of the loft space.



Would that be allowed under the buiding regs?



Cheers


isulation, inherited when I bought the house is hit and miss


Then put celotex between the rafters and under them - I did.

If you have 4" rafters, and the tilers use a breathable membrane, you can typically have 3"/75mm between the rafters leaving a 25mm air gap under the tiles.

Another 25-50mm under the rafters and you have the equivalent of 8-10" glass wool. And your floor is clear (you could still have 4" glass wool on the ceilings between the joists).

Throw it away. If it's been in the loft for years, you don't need it.

Are the building regs really the issue? I'd have thought it more important that you get the best advantage from the insulation job. It's not like anyone is going to pop round to check your insulation to see if you're up to regs. Presumably the hatch could have something put on it, like a slab of celotex, if the ladder doesn't stop that, and that would insulate most of it.

Except for the BCO if the OP/OP's roofer is doing it by the book.

If the roofing battens are being replaced, you could consider doing a warm roof. If you can raise the roof height by a few inches, you put celotex between the rafters and new battens. Otherwise, you could look at something like TLX Gold - insulating replacement for sarking, to be used with some loft insulation.

On 11 Jun 2014, snipped-for-privacy@cucumber.demon.co.uk (Andrew Gabriel) grunted:

Doesn't Tim's suggestion of celotex between the rafters presuppose it's has to be a warm roof, though? Otherwise the celotext won't work?

Technically it's still a cold roof as the top of the woodwork is cold. This is why you have to take care to avoid condensation issues.

A warm roof is where the whole structure apart from the covering (tiles) is warm.

"Warm Roof" is a building term which technically means the insulation is beyond the rafters, i.e. the rafters are warm too in cold weather. It benefits from not losing headroom below the rafters, and they are themselves much better protected from damp/condensation/etc.

When I asked a couple of roofing firms about replacing my roof, I was told that the loft insulation was part of the same 'thermal element' (is that the term?), so the insulation would have to be up to standard. I've ~30cm of glassfibre over 1/3rd. of the loft and ~7.5cm+bords over the rest, so I'd have to lose ~20cm of headroom to do the lot. Fortunately the roof was sound and a few repairs fixed it.

Please stop telling the truth. I like my unusable rubbish collection which she keeps trying to evict!

Huge put finger to keyboard:

Didn't realise you were female, Huge.

I'm not. But I have recently had to clear the houses of two elderly relatives, and I'd like to save other people the pain of this. I've been chucking stuff away ever since the first house clearance and the second one just reinforced the point.

Huge put finger to keyboard:

I know. Should've added a smiley.

I keep boxes that things come in, just in case. I'm sure I've got boxes for things I threw out a decade ago...

Ditto! :o)

Oh, there's nothing wrong with keeping those. The removal man heaved a huge sigh of relief when I told him I had the boxes for the TVs, stereo & the like, when we thinking of moving house a few years ago.

Me too. I'm about to become semi-retired and one of the things I have on the list is to clear out the eaves storage space full of boxes. (The loft is unsuitable for storing things in.)

No - few BCOs would try to insist on new build standards on a renovation job. as long as it is better (or at least as good as) what went before that's generally fine.

Thanks - a point I can argue if necessary. If the BCO isn't too worried, the roofer is probably being cautious - it's not a job that can be out of sight...

That's the *only* thing I allow in the attic. Otherwise I know it would be filled with things which will never be used again.

Wish I was so disciplined about the house. However, I have just taken 3 perfectly working VDUs to the tip, which will never be used again. (I can buy second-hand LCD replacements, physically much smaller and lighter and clearer and with bigger screens for £10.)

You're never going to use the tip again? How will you dispose of your junk?

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