Dry lining over a damp patch?

[ellasmum]

Hoping for some quick advice, I have 2 damp patches on a 4th floor gable end wall. House was rerendered 2 years ago but these patches (1 about 3ft below other) won't dry out. I have been advised that the plaster should come off and be redone, but had plasterer around tonight for a quote and he reconed dry linig would work. My worry is the damp would just find its way through, it's not bad, no mould.

Any ideas?

[Dan the man]

It would come through the plasterboard, the adhesive that sticks to the wall and plasterboard will eventually show the damp through, try and solve the problem first, if you've done everything and its still damp then you could battern the wall and screw foilback plasterboards to it and it wont get through that, I've done that before.