boarding out a loft plus adding extra insulation

[Mark]

Hi

Having given into the need to board my loft please advise re my thoughts as to the best way forward

there are 2 4by2 timbers running north/south with 4by2 timbers at equal spacing running east/west below them

Given that the target depth for insulation is now 8inches, I was thinking of adding extra 4by2 timbers laid on top of the existing east/west timbers then adding extra insulation (Mineral fibre or fibreglass matting )then boarding.

What is the best method for attaching these extra timbers?

At the eaves how much air gap should I allow? One thought is to hold the insulation back with thin plywood tacked to the trusses (shaped to fit down to the ceiling.

[ipellew]

Hi;

I did my attic, but not to the 4inches you speak, I used 2*2 but relied on the screws through the chip board (B&Q type) into my newly layed 2*2 after laying an extra 2" of glass fibre Insulation. I rather regret not using vermiculite as the extra insulation. I successfullly used Verminulite on an old farm house I refurbished years ago and is much more workable, handlable than glass fibre. I chatted to there rep at the recent Tools show at Donnington Park and they say its available from Jewson.

Having "done" my attic, of course I have had to go back up and update the electric etc. (as one does wife a partner that wants this un that), but my screwed floor stood up to my crowbarring a couple of sheets.

I did go to the length of drilling and countersinking each screw, but then I used only 2 per joist and the tongue and groove seems to stand up to all my moving and storing this un that OK.

Regards Ian