Help completing a Garden Room

[John D v2.0]

Interior construction is to be rockwool insulation, breathable membrane, plasterboard and then plastered to finish.

Warm side of the insulation must be a VCL not a breathable membrane, only the cold side should be breathable.

 

[efunc]

ahh, thanks, that wasn't included in my original build. Just reading up on it now. I notice it is used in walls, ceilings and floors, in addition to DPM etc

https://www.permagard.co.uk/advice/installing-vcl-vapour-control-layer

 

[John D v2.0]

from your link it sounds more like they're going for good airtnightness. This is important for the effectiveness of insulation, but it doesn't have to be totally perfect all joints taped for condensation reasons, as long as it gets more permeable towards the outside of the buildup (so the water can dissipate)