Rising Damp?

[Eleanor Nash]

I live in a 1920’s semi-detached house with solid walls.
As we’ve moved into winter/wetter weather I’ve noticed a tide line beginning to appear on part of the hallway wall leading to the stairs. The other half of the hallway closer to the front door does not have this issue.
We have also recently realised that the inside of the cupboard under the stairs is very wet - the walls have visible moisture and are going mouldy (brick floors under the carpet).
This entire wall is on the detached side of the house. There looks to be an injected DPC externally and it looks as though the internal hall wall has been replastered to a height of approximately 1m previously.
I am unsure if there is a DPM under the laminate flooring and I am unable to remove the skirting board to check if the plaster reaches the floor.
I have been advised that this is rising damp and the DPC has failed.
Is this correct?

 

[foxhole]

External photos ?

 

[flameport]

There looks to be an injected DPC externally and it looks as though the internal hall wall has been replastered to a height of approximately 1m previously.

Damp 'experts' have been in, failed to identify the problem and sold someone a load of expensive injected nonsense. Unsurprisingly the problem is still there.

I have been advised that this is rising damp and the DPC has failed.

No.
It's some much more obvious cause, such as leaking pipes (like those to the left of the photo), vegetation/junk piled up outside, exterior ground level too high, drains blocked/broken, guttering or downpipes blocked / failed / missing, and so on.

Those small plastic tubs with moisture absorbing chemicals in them will do absolutely nothing, don't waste money on them.

 

[^woody^]

It's clearly damp, and it is rising. The issue is the cause.

If it's permanently damp to that height, look for mains or heating pipework leaks.

If the height varies (especially related to damp weather), and you can see lines from various heights, then suspect damp from the ground or the wall.

Black mould can indicate condensation moisture.

Get a survey from an independent surveyor, not one that works for a damp treatment company, or one that has any interest in the remedial work he may recommend.

 

[Eleanor Nash]

It's some much more obvious cause, such as leaking pipes (like those to the left of the photo), vegetation/junk piled up outside, exterior ground level too high, drains blocked/broken, guttering or downpipes blocked / failed / missing, and so on.

The previous owners did store their logs/coal along the side of the house, in the area which would be to the other side of this damp area. However, this was all cleared in late September - I assume that the wall wouldn’t hold onto moisture from this for so long after?

Everything else you’ve mentioned has been checked already, I’m at a loss!

 

[Eleanor Nash]

It's clearly damp, and it is rising. The issue is the cause.

If it's permanently damp to that height, look for mains or heating pipework leaks.

If the height varies (especially related to damp weather), and you can see lines from various heights, then suspect damp from the ground or the wall.

Black mould can indicate condensation moisture.

Get a survey from an independent surveyor, not one that works for a damp treatment company, or one that has any interest in the remedial work he may recommend.

Interesting. The dampness has only appeared since the weather has become poor. However, does not vary in height at all, even with use of a dehumidifier so perhaps timing with the wet weather is purely coincidental.

 

[^woody^]

There are test available to determine if the moisture is fresh or ground water and if its surface or further in the wall structure. Be wary of anyone who tries to diagnose this with a damp meter.

 

[JohnD]

Is the floor concrete, under that laminate?

Is the pipe the incoming water supply to the house? Is it buried in the floor? Does it continue along the passageway to a rear kitchen? Is the wall wet next to it? What is the pipe made of? How old is it? Has it reached the age to start leaking (80 to 100 years)?

Do you know a young person with good hearing, undamaged by loud music, power tools or raucous engines? Do you know where your indoor and outdoor stopcocks are?