Attic Insulation

[derryman]

What is the best material to insulate my attic, some say wool is best others say fibleglass, mate of mine said there is a new eco-wool insulation which is recycled and better than fibre glass?

[terambulan]

Think fibreglass.

Wool would attract moths and could be crawling in no time.

[buildersmate]

'better than fibreglass'?
Better in what way - more environmentally friendly, cost for the amount of heat retained?
Fibreglass or rockwool are pretty much equal to each other. You can buy rigid phenolic or polyurethane slabs (Celotex or Kingspan) which transmit only one half the amount of heat through them (for the same thickness of material), but they cost more than 2x fibreglass of equivalent thickness.
If you therefore have the height in the loft to fit fibreglass it works out cheaper (for the same impact), but if you are limited in thickness you can squash in, you might wish to use a rigid product.