insulating loft end walls

[john250]

Wanting to insulate gable /end walls (1 external and 1 connected to neighbour).

If building a stud frame, can you use rough sawn treated timber (meant for fencing) as that's is all I can see that's around 100 x 20mm wide.

Or does it need to be C16? There's loads of 60mm C16 stuff lying about (but too narrow for my 95mm of insulation) and it seems to be really heavy. Thinking fencing would be less weighty on floor.

Also, can Celotex touch a brick wall or does there need to be an air gap? Will be using foil back plasterboard. Thanks

 

[freddiemercurystwin]

If its a cavity wall on the external side then fill your boots. The party wall is effectively internal so no issues their either.

 

[john250]

Thanks for that. Unfortunately the external wall is not cavity - just single brick (freezing) so maybe in that case cheap fencing wouldn't be hardy enough and I probably do need air gap on the external 1!?? Drat!

 

[geraldthehamster]

The timber doesn't need to be C16. C16 is a structural grade, and you're not using it structurally.

Cheers
Richard

 

[john250]

Many thanks!