Plastering a new block wall

[Roberto2019]

Hi, the internal walls of my new extension are Fibolite blocks (I assume can be considered the same at Thermalite).

Regarding the plastering - I would like 'proper' plastering rather than dot & dab plasterboard.

Questions:
1. I'm guessing a fully plastered wall is more expensive than dot & dab / skim? Any ideas by what factor?

2. For a fully plastered wall, what is the standard depth of of the plaster? I'm am thinking about how far proud of the bare wall should my elec socket back boxes be.

Many thanks

 

[motorbiking]

Have you factored in the heat loss requirements? Drying time for painting etc. Depending on the quality of the wall, it shouldn't be any thicker than dot and dab. bonding coat around 8-10mm top coat 2-3mm.

 

[foxhole]

Should be using insulated plasterboard unless you have exterior insulation .?

 

[Roberto2019]

It's a cavity wall, 100mm will full fill dritherm insulation... built summer 2021 if that makes any difference? First I've heard of having to insulate the inside as well...?!

 

[motorbiking]

So you have brick + 100mm drytherm + thermolite? I think you will need plasterboard on dabs to hit the required 0.19 U, that was in force. If you want to comply with the June 22 regs, you will need insulated plasterboard.

The Dab cavity is part of the spec. 100mm of PIR instead of Dritherm would have just got you there without the PB on dabs.

 

[Roberto2019]

OK many thanks for that. Sounds like I need to do some investigating.

Cheers