Improving Loft Insulation

[D_Hailsham]

My loft has some insulation may be 100mm. I looked up at the roof just now and noticed that there was not the even covering of snow you would expect from a well insulated roof. The problem is that one end of the loft has been boarded over to provide storage - suitcases, Xmas decs etc.

I would like to add extra insulation but retain the storage at the same time. This obviously means raising the flooring by 100-200mm. What's the best way of doing this?

Is there a product which will give the same insulation as the Fibreglass/ Rockwool type mat, but is thinner? Knauf used to have a product called Supadeck, which was foam backed mdf, designed to lay on top of existing insulation. I can't find anything about it on their site now. Does any one know what happened to it or does anyone else make a comparable product?

 

[Deluks]

Make your own. Lay some board insulation down, poly or PUR, then lay t&g chipboard over it, with the tongues glued.

For the rest of the loft, add another 200mm of insulation roll as top up.

 

[D_Hailsham]

poly or PUR,

poly = Polystyrene
PUR = ?

I think Knauf have stopped making Supadeck. They now have a product which can be laid under chipbard called Polyfoam Spaceboard.

DIY sounds a good idea. I was going to lay 200mm rolls over the rest of the loft

 

[JamesBlonde]

B&Q were doing the knauf stuff last time I looked before Christmas - think it was around £20 for a pack of 4. They were also doing their own make tongue & groove chipboard loft boards with a huge wedge of insulation glued to the base for £5 a board, which worked out cheaper - I've just done half my loft with them!

Not the easiest things on the planet to fit if you're not careful, and if you end up indenting the polystyrene on the beams and therefore all the boards not being on the same level and the tongue not meeting the groove...!

 

[DJM]

Depends on how much you want to spend, but Kingspan or Celotex rigid phenolic insulation will be approximately half the thickness for the same insulation performance in comparison with wool. It's not cheap, but if you buy in bulk then it might be the answer

 

[noseall]

poly or PUR,

poly = Polystyrene
PUR = ?

I

knauf, celotex, quintherm etc.

 

[mointainwalker]

PUR = Polyurethane