Insualted plasterboard for extension

[Thermal786]

Hi,

I’m doing an extension, I’ve got double wall cavity 100mm brick, 100mm celotex and 100 block.

I was under the impression that the internal plasterboard needs to be thermal insulated. But I can’t see it on my building drawings.

It states 12.5mm plasterboard which is standard?

Any thoughts? Or am I getting it confused with new build regulations

 

[jono_h]

If you’ve got 100mm PIR in the cavity then you probably don’t need anything else internally.