Removing plaster off wall due to damp

[Danny R]

Hello,

I was wondering if you could offer any advice.

I recently had a damp issue and was advised by a contractor to cut of 1m of plaster, damp proof membrane and plasterboard and skim. After removing the plaster, this is what I found; see pics.

The brick wall is in a terrible state, with patches and obviously the removal of the chimney stack at some point. The builders simply plasterbaorded and reskimmed.

Question - what would be the normal procedure to repair this wall. Is it OK to simply plasterboard back up or will there be issues further down the line. Am I overexaggerating?

Any advice would be helpful

 

[JohnD]

You also need to find out where the water is coming from, and correct the fault. Often it is a drain or pipe leak.

Please show the other side of the wall.

Indicate where the DPC is.

Is the floor wooden or concrete?

I would be inclined to clean out all the loose material and use mortar to repair and fill the brickwork

 

[Danny R]

Pics attached of the outside wall - the floor is wooden and it is a victorian end of terrace, this wall is an outside wall.

 

[Alastairreid]

Looks like its been an ongoing problem.
I would point any loose stuff and use a cement render scratchcoat with waterproofer.
I would remove the black tar from the outside as well.

 

[Danny R]

Do you mean a cement render scratch coat for the exterior wall? Yes I have no idea why the previous owners tarred the side wall.

Oddly enough (we have only recently moved in) the survey said there was no damp at all

 

[JohnD]

I have no idea why the previous owners tarred the side wall.

it is usually an attempt to hide (it does not cure) damp at the bottom of a wall.

in fact, since it prevents evaporation from the surface of the wall, it makes the damp worse.

I also see the wall has been drilled for chemical injections, in a futile attempt to cure the damp without repairing the defect that causes it.

As you have a wooden floor, lift it up and see if the void has been filled with rubble hidden by the builders when the chimneybreast was removed. If so, dig it out, clear the airbricks all round, and the air currents will reduce damp. You will also be able to see what parts of the wall and ground are damp, for example if water is puddling outside, or escaping from a broken pipe or drain (it probably is).

you can see the concrete yard has a lot of moss or algae displaying long term damp, and the side wall starting at the gatepost has a high water mark. The whitish mark is lime bloom from hard water, possibly from a leaking water pipe, and reaches a long way up the wall. Look for the highest point in the mountain-shaped wet patch, and the leak is probably under it. I can't see any airbricks in the wall, but there should be some (they may have been buried by the concrete path) As this is an end of terrace the drains probably run under the concrete path and are probably cracked and leaking (since 1940).

What downpipes, soilpipes, gullies and manhole covers can you see?

Can you see the dpc?

look for leaking or spilling gutters. They will be the easiest of your problems to fix.

 

[JohnD]

congratulations, by the way, you have a good example of long-term damp concealed by plasterboard and paint to hide the problem from the buyer.

 

[Danny R]

Past the gate is the side of our house where all the gutters and downpipes end up into a single gully; other than that, Thames water survey map doesn't highlight anything running directly underneath the concrete floor of the end terrace, but they could be wrong - seems a bit strange why you wouldn't put drainage down this alleyway to be fair.