Width of external wall with 2023 building regulations

[JimExtension]

With the 2023 building regulations changes it looks like the external wall width (from exterior brick to finished plastered internal wall) for a new extension would be:

102.5mm - exterior bricks
150mm - cavity for standard insulation (unless using some higher performance / more expensive insulation)
102.5mm - blocks
10mm - dot and dab adhesive
12.5mm - plasterboard
3mm - skim plaster

= 380.5mm

Does that sound right?
Thank you.

 

[noseall]

= 380.5mm

Does that sound right?

Yes - other than pedantry tells us the changes were June 2022.

 

[JimExtension]

Thanks! These are thick walls then!

 

[noseall]

Thanks! These are thick walls then!

Ridiculous

 

[freddiemercurystwin]

On an incredibly tight site I've just specified an external wall of 290mm (U Value 0.18), 75mm inner skin mind + wet plaster.

 

[freddiemercurystwin]