1st Floor Extension Insulation question

[TheHandyAndy]

Hello all,

I'm currently building a first floor extension on the side of my house. The underside of the extension is open, to park the car under etc...

Question is, what is the best thing to use to insulate the roof of the carport / extension floor? Should I just fill the areas between the joists with something like rockwool?

Thanks,

Andy.

 

[DAZB]

If you have any architect's drawings then it should specify on them what is to be used. Failing that I would recommend 100mm Kingspan friction fit and also remember that if you are using it as a garage then the ceiling has to have two layers of staggered plasterboards and then skimmed to comply with fire regs.

 

[mointainwalker]

I think , economically, fibre wool is unbeatable, even more so if you can still buy subsidised product.

Only reason to use Celotex would be to meet Building Regs

 

[TheHandyAndy]

Thanks to both for the replies.

I've had a good read of the architects drawings, it states 50mm Kingspan Kooltherm K3 topped up with 100mm rockwool or similar.

Thank you for taking the time to reply. And yes, I did manage to get loads of subsidised rockwool from my local B&Q