Damp Problem - Who to Approach

[bigalxyz]

I seem to have a damp problem in part of my flat in Hackney, East London. No mould growth, but areas of powdery residue on the drywall. The brickwork behind is damp (have cut a hole in the drywall and used a test meter on the bricks). The cause isn't obvious.

There are lots of damp treatment firms but I'm wary after hearing lots of stories of companies offering free surveys which invariably lead to a BS diagnosis of rising damp which can only be treated with their expensive treatment (which then fails to work). I could ask a RICS surveyor to diagnose I guess, but I imagine that could get expensive. Are there *trustworthy* damp treatment firms out there who could diagnose & fix the problem properly? How do I find one?

(not necessarily expecting specific recommendations for providers, although if anyone does have someone they trust in this area, I would certainly be interested to know)

(the leasehold management company will be paying - not me personally - because it's affecting the fabric of the building, but I'm a director of that company)

Thank you.

 

[jacko555]

Minefield. Also a diy.

Many causes of "damp" Are you below ground? Top floor?

Is it condensation - warm moist air getting behind the plasterboard and condensing on the cool bricks? Was the plasterboard put in to mask the damp? How long have you lived there?

What's on the other side of the wall? Any toilets, radiators, buried pipes, gutters nearby?

Is it just one wall? All walls?

What kind of brick wall? Cavity or solid? And cavity wall insulation?

How old is the building?

Loads photos will help of both sides of the wall and wide shots.

 

[bigalxyz]

Thank you. To try to answer your questions:

Basement flat, below ground level.

Re condensation - two rooms are affected by this. There's a little bit of condensation on the window in one of the affected rooms in the winter (possibly caused by my lodger drying her clothes in there, which I might suggest she doesn't do for the time being), but not the other.

I've been here for 19 years but I've only noticed the problem in the last few months.

It's an outside wall, so behind the plasterboard (maybe a 3 inch gap?) are the original bricks. No toilets or gutters nearby. There are radiators nearby, but all the pipework is close to the floor whereas the damp is all about 1.2m-1.5m above - at floor level everything is dry.

It's not all my walls that are affected, it's just the outside walls at the front of the flat (two adjacent bedrooms). There's another identical flat on the other side of the basement and there are no problems in there at all.

No cavity wall because of the age of the building (dates back to approx 1875). No sign of insulation between the bricks and the plasterboard.

I don't think there are any water pipes in the front rooms of the flat immediately above, except a toilet overflow which is some distance from the affected area. I might need to double check this though ie ask the guy upstairs for access to inspect more closely.

Will try to post some photos later.

Edit: have ordered a couple of hygrometers - will put one in each of the affected rooms when they arrive.

 

[jacko555]

Aww man this is tricky.

If just the front, and fairly recent I'd be looking for broken / overflowing gutters saturating the brick, or drains out front.

I guess the good sign is this is recent, then it's not a long standing fundamental issue with a near 150yr old basement with solid walls.

Far more experienced people will give their advice, however, I reckon a good look out front is a good start

 

[bigalxyz]

There are certainly problems with the way the building deals with rainwater. The big box gutter on the roof works fine, but if it rains heavily and it's coming from the north, it just hits the side of the (north facing) building - 5 storeys high - and runs down to the basement. Quite a lot of it sometimes.

Also the outside of the building is rendered. I don't know, but I'm guessing it was done with modern gypsum plaster rather than the old skool lime stuff (which I'm told - by my mate upstairs who knows about these things - is a better match for the type of bricks that the building would have been constructed from), so probably not breathable - I wonder about moisture getting trapped in the brickwork behind the render...?