insulating my rafters

Doglover88

whats the best type of insulation for rafters? they're going ot be plasterboarded over once insulated but i have no idea what type to use

any recommendations?

bcoman

Depends on several things - how deep are the rafters and where are they - in the loft or a sloping ceiling to an extension? Regs have changed recently regarding U values and you need to design to avoid condensation problems

Doglover88

cheers bcoman

theyre in the loft, and are 4" deep. Any advice?

many thanks in advance

plumb1_2

Kingspan is the product you want, make sure you have good ventilation, or you are liable to get damp/condensation=rotten timbers!



http://www.insulation.kingspan.com/newdiv/literature.htm

Poppycat

I did ours with Kingspan and screwed and glued it to the rafters leaving the gap between slates/rafters for air to circulate.

FilthyLuka

glenbat wrote:

whats the best type of insulation for rafters? they're going ot be plasterboarded over once insulated but i have no idea what type to use

any recommendations?

are you looking to use the roof space as an extra rooms/space - be careful as there are many health and safety regulations to be met (for good reason)

you may need building control involvement from your local council


kingspan is probably the best performing insulant for its size but you will need to heep a 50mm ventilation gap over the top and you will need to install larger soffit ventilation and ridge ventilation to avoid condensation and rotting your roof timbers

windym_2

We used tri-iso but it is expensive. It is like a sheet of foil with many layers of insulation. http://www.just-insulation.com/super10.html?gclid=CN6StYnW7YYCFQ5LMAod6z74ag

nelly_2

Yep when ever I plaster a loft conversion theres always Kingspan in it.

catwoman

Hi where can I buy kingspan? I live in North yorkshire.

Poppycat

I live in North Yorkshire too. I got mine from builders merchant, MKM. It was at the time £44 for 11 sheets about 1inch thick

http://www.mkmbs.co.uk/

catwoman

Thanks poppycat but I can't find kingspan on the website,I think I'll have to ring up.