Damp in 200 year property

[Sunnyside]

Hi
I have had a survey report (homebuyers) on my property stating basically damp everywhere (rising), DPC failed and damp coming down the chimney stacks.

The house is solid walled, ground floors are ashphalt. It has had a chemical DPC in the past. A couple of years ago I had a Structural Surveyor inspect and he only found damp in one area - I then had the plaster chopped off etc etc as per his recommendations.

My question is the Homebuyer surveyor used the 'prong' meter on the skirting boards?! Surely he should have used it on the walls?

Also there is a spot of damp on an internal (solid) wall about 1m up off floor level. This is about the size of a saucer and is circular and the plaster has bubbled / has some salt deposit on there. (This was replastered with a waterproof mix a couple of years ago - spot is where the new plasterwork is) The confusing thing is I canot figure out why - one side of the wall is the lounge (the side thats bubbled) the other is inside the understairs cupboard - no sign on this side.

Any advice appreciated - I did think about chopping out the saucer sized part and injecting in some DPC then plastering over?

 

[^woody^]

A damp meter is designed to be used on timber, not walls.

For the other damp patch, then if there is no pipe leak in this location, then the problem relates to the previous plaster repair - a reaction with the plaster/salts. It needs replastering and sealing (PVA) no need for damp treatment[/url]