Damp wall in bathroom

[scottyhillman]

I've just taken out a shower cubicle so I can replace it (nice easy 1 day job!!) and when I've lifted the tiles, most of the lime plaster/mortar has come away and the bricks underneath are very damp. For about 1m up from the shower tray is fine as it has some sort of creamy white plaster there (a renderguard type maybe?), but above that is a mess!! The shower was fitted into the corner of 2 outside walls, but the walls beyond where the shower cubicle was is fine, so I think that the damp has come from the house side and the tiling wasn't up to scratch in the first place.
My question is, as I am doing up to sell, what is the quickest, easiest way to treat this so I can tile on top and refit my new shower cubicle?

 

[masona]

Sounds like to me the shower area wasn't tank. Are you sure the plaster where the tiles was is not showing any sign of black mould, damp or crumbling?

Doing it the quickest and cheapest is not really fair on the next new owner

 

[scottyhillman]

Quickest and easiest I said!!!! I want to do a good job for the next owner, but I'm in the forces and getting drafted away from here, so need to complete job and get house on market asap!! No mould or anything on the plaster that has stayed on the wall. Thanks for any further advice in advance

 

[masona]

Quickest and easiest I said!!!!

Doh!!!

Start on the outside first, check the gutter not leaking, overflow pipe internal & external, hairline cracks roofing tiles, water/heating pipe, lead flashing, chimney problem and so on.

Do you have a shower mixer or joints that maybe leaking behind?