best loft insulation?

Doglover88

cheers gromit
is it ok to plasterboard the rafters though? leaving a gap round the bottom for it to 'breathe'? was going to use the aluminium back plasterboard to improve the water resistance of it should the roof leak slightly

gromituk

No, I'd say that was a bad idea. If the roof leaks, you want to know about it. If you plasterboard the rafters, the water might run into them and rot them with you being none the wiser.

GSXRCarlos

The placement of insulation will all depend on if you want to create a warm roof or a cold roof, warm roof, insulation to underside of slates - normal if you're converting the loft. Cold roof is where you insulate the floor (of the loft space) and leave the actual roof as it is.

I suggest increasing the thickness of your insulation by running new timbers at right angles to the existing joists, and packing with upto 300mm of insulation, then chipboard over the top, under no circumstances should you ever squash the insulation under floorboards etc

27col

robnye wrote: »

if the existing fibreglass insulation is pretty clean , ie not a dirty grey colour, then just lay new fibreglass over the top. as the recommended level is now 250mm (i think,) then the more the better

make sure you use gloves and have a face mask.........

for more info. try giving your local council a call

It does not matter how dirty the existing fibreglass is. Just put more over it. The latest plastic bagged stuff is very easy to lay. With virtually no irritation from particles. You will probably not need to board the whole loft. So have a good clear out and just board the minimum area that you can manage with, for storage. Have 100mm in the area under the boards and full thickness elsewhere.

pqr

Hi,
Anyone used this? Looks comparable to a rockwool to me, but is cheaper, although I know little on this subject, i.e. nothing.

Made from 90% recycled plastic bottles, Totally itch free, R-value: 3.75, 150mm thick
Overall dimensions: (L)5.3m x (W)370mm x (T)200mm
Coverage: 1.96m²

Regards, Phil

gromituk

You need to compare its R-value with that of conventional insulation to see if it's as effective inch for inch.

nickcardwell

pqr wrote: »

Hi,
Anyone used this? Looks comparable to a rockwool to me, but is cheaper, although I know little on this subject, i.e. nothing.

Made from 90% recycled plastic bottles, Totally itch free, R-value: 3.75, 150mm thick
Overall dimensions: (L)5.3m x (W)370mm x (T)200mm
Coverage: 1.96m²

Regards, Phil

used it myself.

r value is better than the itchy stuff if i remember rightly.

The stuff is like a fleece jacket you get.
Non itchy.

Gambler

I want to put 100mm insulation between the rafters before I board over. Wickes has a buy 1 get 2 free at the moment i.e. £10 each or Hombase are doing the space combi for a similar price.

Which is the best or are they fairly similar?


Thanks

gromituk

See my previous posting...

Gambler

gromituk wrote: »

See my previous posting...

R values are the same. Just wondered if anybody had personal experience of the product.