Internal Wall Insulation Queries

[Mr Sparkle]

Looking to insulate a solid wall and had some queries

1. Is there a recommended insulation thickness backed up by building regs?

2. If one was to purchase the PB and PIR Insulation separately, what is the best/recommended product to use to stick them together?

3. When fixing insulated PB to the wall, due to damp transfer, is the general consensus to use Plasterboard Adhesive Foam as opposed to dot & dabbing with plasterboard adhesive?

 

[noseall]

1. Is there a recommended insulation thickness backed up by building regs?

Upwards of 50mm

2. If one was to purchase the PB and PIR Insulation separately, what is the best/recommended product to use to stick them together?

Foam or mechanical fix.

3. When fixing insulated PB to the wall, due to damp transfer, is the general consensus to use Plasterboard Adhesive Foam as opposed to dot & dabbing with plasterboard adhesive?

As above - either foam fix or use battens.

 

[robinbanks]

1. Is there a recommended insulation thickness backed up by building regs?

Yes; I believe the present regs for renovating an existing wall are that you should achieve a U of 0.3 if it's worse than 0.7. If using 0.022 lambda PIR/PUR insulation boards on eg a 9 inch solid wall, less than 20mm of PIR means you're below that worst case, and you should be installing for a total of 60mm to achieve the improved value, but the calc varies according to the existing wall thickness and structure. If it's classed as a new wall it needs to be 0.18, or 110mm