the (expensive) space blanket in silver rolls is actually yellow fibre, which sheds dust and loose fibres when the cover gets torn.
I only use Knauf mineral wool now, which is treated with Ecose and has a soft feel, the treatment prevents it shedding fibres. It is sometimes own-branded in the sheds, but will alweys have the "Ecose" name on the packaging. It is brownish, not yellow.
You can cut it with a breadnife to fit the timber spacing.
Last year there were lots of energy-saving subsidies on insulation, but there don't appear to be now.
See what price your gas and electricity company, and local council, are offering to supply and fit, they might still have subsidised schemes on offer. Look at BG first even if you are not a customer.
I told you it was exciting at chez sleepdodgers... I have moved to an old place that heats the surrounding area it's retention is so efficient... I want to buy the space blanket silver wrapped lift insulation as our eaves are tricky to access an we would be able to open hatch and roll, safer for DS and allergy prone dh... But... At £16 small roll in B&Q will cost alot Defo needs doing and will be worth it (won't it?) but do you know anywhere which is cheaper?? Tried other retailers and amazon (&ebay!) This kind of thing (sorry on phone can't link) http://m.diy.com/mt/www.diy.com/nav/build/insulation/loft-insulation/space_blankets?&listerGallery=false&un_jtt_redirect Will send virtual or to one who saves me most cash!!!