Plastering inside garage - single skin walls

[28steve]

I plasterboarded and skimmed the internal walls of my garage about three years back and one of them is suffering with damp and causing unsightly marks and basically make the plaster and boards soggy. I'm going to pull it all down again but how do I remedy it?
It's just a room a use as I gym but I like it looking clean and tidy rather than exposed or painted brick. It is a single skin wall.

 

[PrenticeBoyofDerry]

To remedy this, you would require to investigate where the damp is coming from. It could be a number of issues, I assume this is a water ingress problem rather than a condensation problem.
So the fabric of the garage needs to be inspected for leaks, also plasterboard will soak up water from the floor level, if you have not left a gap between board and floor.

 

[Alastairreid]

How did you fix the sheets to the wall and did you install a vapour barrier?

 

[28steve]

I dot and dabed the wall, I didn't use vapour sheets.

I assume the damp is coming in as it is a external wall with no cavity

 

[28steve]

Can anyone else help with this?

 

[roy c]

Did you render and paint the outside of the garage? If not you wont stop the water coming thru.!! especially if it is single blockwork..

 

[noseall]

You will never prevent damp manifesting itself beyond a single skin structure, unless you build a separate insulated skin inside.

There are simply too many ways it could fail, i.e. cold bridging and penetrative damp etc.

There are several ways to achieve a better result some more successful than others. All are dependant upon how much space you wish to lose and how much you want to spend.

Low end jobby would be to fix 25mm battens, with 25mm insulation between and fix ?mm depth insulated plasterboard to the battens. The thicker the better. Polystyrene would be cheaper but a lot less effective.
There is also V.B. to consider - again, all dependant upon budget.

 

[28steve]

I realise I'm not going to solve the problem just wanted to curb it as much as possible.

So if I use batons what kind of insulation should I use? I was worried that I would be trapping the moisture behind the wall by doing this?

 

[28steve]

Did you render and paint the outside of the garage? If not you wont stop the water coming thru.!! especially if it is single blockwork..

Nah I haven't done this, this is in a neighbours property and relations aren't at a point where I can go and render their walls
Unfortunately.