Damp party wall

[quintain]

Hi.
I need to deal with a "rising" damp solid party wall of a 1890s small mid terrace.
(I put rising in quotes as I subscribe to the waste of time of most chemical etc treatments)

The adjoining property has a floor level of 10" or so higher than the one I am dealing with.

I am considering removing plaster to about 20" or so and replacing with insulated plaster board using dabs, then over floating/skimming.

My thoughts and theory are that dabs will hold the insulated board (when it won't hold foil backed board) and a small airflow will be allowed between the board and the wall.

I would welcome your thoughts on my solution to the slight damp problem.

 

[JohnD]

what sort of floor is it?

might be better to fix the leaking waterpipe.

 

[quintain]

what sort of floor is it?

might be better to fix the leaking waterpipe.

Hi JohnD

I don't understand your point about the waterpipe.
The floor is timber but will be replaced with solid; 4" slab over some insulation.

 

[joe-90]

JohnD knows these things. We call him the Oracle.

 

[JohnD]

A party wall is not going to have much wet from dripping gutters or rain, or raised flowerbeds. If it is wet, where is the water coming from? Condensation not common on a party wall. Unless there is a stream under the house, it is most likely coming from a leaking pipe. Either a water supply pipe, or a radiator. Sometimes a drain or waste pipe, though most bathrooms and kitchens have these againt an external wall. If this house and/or the house next door have water meters, look and see if the bubble is in constant motion.

 

[Burnerman]

A property of this age is almost certain to have earth floors, and rising damp in party and sleeper walls is common.
Can you lift the floor boards in the proximity of this wall, and see if there is any attempt at damp proofing (likely to be slate soakers or poor quality felt).
My guess is the exposed brickwork will be wet and needs chemical treatment.
I'm not a great fan of injected DPC's either, but it could be the best way forward.
John

 

[joe-90]

I'm with JohnD on this one. If it's not been damp for the past 100 odd years then why is it now?

 

[JohnD]

It is very hard to make "rising damp" rise more than a few inches in bare brickwork, even when it is standing in a puddle or river.

Yes, it will be interesting to look under the floor.

 

[Burnerman]

I'm with JohnD on this one. If it's not been damp for the past 100 odd years then why is it now?

Chances are, its been damp for much longer than anyone realises!
John

 

[Burnerman]

It is very hard to make "rising damp" rise more than a few inches in bare brickwork, even when it is standing in a puddle or river.

Yes, it will be interesting to look under the floor.

Not too sure about that one John - in my holiday cottage, (earth floor, circa 1920's) the sleeper walls (4 courses) are damp until the DPC is reached below the wall plates.
I make sure there's a gale blowing below floor board level!
John

 

[stevethespreader]

I'm not a great fan of injected DPC's either, but it could be the best way forward.
John

bare in mind if you go for this you have to serve a notice to your neighbour as the party wall act requires you to serve a notice if any dpc work is done including chemical damp proofing