Tanked wall and condensation

[Steveb21]

Basement built with infill blocks (c35 concrete and rebar).

Tanked internally with KA Tanking Slurry.

Water is not entering basement however walls are attracting condensation. Basement is 2/3 in ground, there are 3 window openings above ground, at approx 1x1m each. These windows are yet to be installed so the area is fully open for venitallation. Tanking was applied approx 3-4 weeks back.

Plan is to put up a metal stud frame (away from the walls), fill with mineral wool, VCL over the stud frame, and then insulated plasterboard on top.

Would this provide sufficient enough vapour control to keep the condensation off the cold basement walls?
Understand i could add a dehumidifier and an extractor.

 

[jeds]

I know they are popular but I'm not a fan of dehumidifiers myself. If you need a dehumidifier to keep the environment at a reasonable RH, summit's wrong.

Your plan sounds ok. I would definitely add an extractor (consider a humidistat) and trickle vents to the windows.

 

[Steveb21]

Trickle vents on the windows, extractor fan (maybe even 2) and a dehumidifier. Basement is approx 50m2.

When installing the wool insulation between the metal studs... should the insulation be kept off the wall (leaving a gap) or should it be pushed up against the wall? As mentioned there will be a VCL on top of the stud (warm side) so there should be not way moisture could get from the wall > wool insulation and through to the plaster boarded finish.

Need to get this right as once its all done and skimmed... it will be a PITA to check whats happening behind the stud work.

 

[jeds]

Standard answer is to follow the manufacturer's instructions for the product you choose but, I can tell you, that all the standard configurations for wall linings show a gap. Typically about 20 or 25mm.