MikeGrahamT21

I plan to re-use the chipboard (loft boards) which are already up there, another plus for using 4x2 so I can line the centres up as i need them. I'll keep looking for cheaper timber, won't be doing it til next year now anyway, as I've too much on at the moment, just trying to make a plan of action. Yeah will definitely be taking a close look at the wiring, i know theres a lot which can come out, as we've replaced it with new stuff. There will be more insulation going on the wiring, but as I said before, theres barely anything flowing through them, as its only LED lighting, so I'm not concerned about that.

you know i thought exactly the same thing about 5mins after i'd written that! lol I sure think thats going to be the most cost effective solution, giving the best overall value (i.e. improvement on u value vs cost).

What i really need to know is, will putting 200KG of timber up there affect anything?

They are the cheapest i've seen actually for the legs. Not fussed about paying for insulation, its cheap anyway, and i've got most of it already. How about my idea with the 4x2 crossing the 4x2 which is already there to allow an additional 100mm for around £136? I think thats going to be cheapest, since i'd probably need over 300 loft legs to do it with those, though at that price it may be do-able, i'll work it out.

Yeah good idea for that bit, what about the main bulk of the work?

Hi, I'm wanting to upgrade our loft insulation, and just wanting some confirmation that my idea is OK. Currently we have 100mm fibreglass insulation between the joists (I've just been up and measured, they measure around 107mm deep), and we currently have loft boards, which I'd like to retain for storage purposes. House is 1968, with traditional roof with purlins, so no crossing timbers in the main storage area. Current U value somewhere around the 0.4U mark. Total space is around 6m x 5m (35m2) (bungalow) I've thought about quite a few different methods, loft legs (too expensive), just laying insulation over and losing storage space (not ideal), and then my final thought... my final idea is to cross these existing joists with more 4x2 joists (we would need 24x (47x100x3m) to cover the whole area at the relevant spacing for the loft boards), and then lay another 100mm fibreglass inside these, giving 200mm overall (i appreciate that's still not up to the regulatory 270mm, but the extra 70mm ontop of the 200mm doesn't bring down U values as much as the initial extra 100mm on top of the original 100mm, and the cost is far greater) which would land us somewhere around the 0.21U mark, so effectively halving the U value for the cost of the wood (£136), and a bit of insulation (i've already got 3 rolls of 100mm, so likely wouldn't need much more). Now this is all well and good, and whilst i do all the work, which i'll do myself, i'm going to ensure all of the electric (lighting) cables which are up there are in good nick, and the circuits are as simplified as possible (and theres a couple of junction boxes which need taking out) (Low energy lighting by the way, so overheating cables shouldn't be an issue). I did however think of one draw back, and that is the 200KG of timber required as extra to what is already up there...now in my mind, this will be absolutely no problems at all, but I'd like a little reassurance before i bring our entire ceiling down lol! Theres not a massive amount of stuff in the loft storage wise, certainly nothing heavy, and no water tanks or anything like that. Any feedback greatly appreciated. Regards Mike