Rising damp identified on survey - what to do?

[potplantsinparadise]

Like it says - I put an offer in on a Victorian rebuild maisonette, and the surveyors have identified rising damp on one of the walls on the ground floor. It would cost around £2k to fix but crucially is on a party wall, so would require permission from the neighbour to do works. I really don't know what to do - the place is nice but this feels like such a ball-ache; also the surveyors don't know why there's damp which also feels unsettling. We/the surveyors can't find a manhole to do a CCTV survey of the drains...

Not sure what I'm asking for here but has anyone experienced similar? Would it be a deal-breaker?

Have you had a proper damp survey? Or just the homebuyer survey?

I bought a ground floor victorian flat with damp. We had a damp survey/quote before purchase and knocked off the cost of the work. It was about 2k and easy to do, just had to wait a few weeks to repaint. When we sold the flat the buyers' surveyor checked that wall and found it to be 'bone dry'.

I wouldn't stress about the party wall issue, works aren't particularly disruptive to a neighbour (I doubt I'd even tell them if it was me).

If it's on the party wall could it be an old blocked up fireplace?

Don't trust a damp specialist - they have a vested interested in making you do damp work like dpc injections which often don't work, especially for old houses. Get a surveyor who specialises in old houses to come out and find the cause first before you do pay for expensive works

Or rather "never work". That entire industry is one big con. 99% of the time it'll be a leak from inside the house, leak from the gutter/roof, or bad choices by the owner (impermeable outside layer on a solid brick wall, not enough ventilation etc).

Hmm there's a theory there's no such thing as rising damp. You would need to know the cause to fix whatever it is too.

Rising damp has largely been debunked, it's all a bit of a con. There will be a leak somewhere

Find the source of the problem, or you won't be able to find the right solution. Lots of 'damp specialists' will claim there is 'rising damp' and charge a bomb to 'fix' it when either it isn't damp, or what they plan to do won't work (or, as in our case, would have made it worse if we'd allowed them to do it). Lots of threads on here about this if you search a bit. A regular contributor called PigletJohn is excellent on it. And check out the 'Heritage House' website.

Thanks all. In answer to questions - damp was identified in the original survey, who recommended getting a damp + timber specialist in, plus a drains survey. The damp specialist who conducted the inspection yesterday identified rising damp. For reasons detailed above, we haven't been able to do the drains survey.

I don't think the cause is an old fireplace on the other side of the wall - I've seen the original building and don't think that's where a chimney was. So no idea what's causing this, especially since we can't get into the bloody drains!

Thanks also for the nod on rising damp itself - it's nothing I know anything about and hate being so dependent on the surveyors for info. Just don't know what to do :(

Rising damp solution No1: if its not too serious, live with it (to some degree, I do), and mitigate it by using a de-humidifer.

Soultion 2. Replaster (up to a height of three feet or so), with LIME PLASTER ('Limelight' is the leading brand). This enables the wall to breath, and any moisture to exist the wall. I have had this done in a couple of rooms in my Edwardian house.....IT WORKS !

'exit the wall.

As for the rising damp naysayers. Sorry I disagree. Moisture will - by capillary action - rise up a wall; there does not have to be 'a source' of water.

If it did not exist, then it could not be cured, by re-plastering with 'Limelight' or another lime plaster, which is an effective solution, as I have proved in my own house (in some walls, where it is a very minor problem I have not bothered to replaster).

it's not going to keep going up by capillary action though surely?
ie even if exists will stop pretty soon?
Have the idea that in the past the idea was put around that it would just keep heading steadily skywards, "eating" the house.

If you replaster, damp will continue to rise (capillary action) through the brickwork. Ordinary plaster holds that moisture; 'Limelight' plaster lets the wall breath, and you don't get the cold feel when you put your hand on it, or a watermark. Messy job to replaster, involving three coats of plaster - but it has worked for me.

ps. Evidence that my replastered walls 'breath' is that the paint starts to flake, and drop off the new plaster - but the wall remains dry. This is because I made the mistake of using ordinary emulsion paint (Dulux). There are special clay based paints, which allow moisture through, and avoid this issue.

On our last house that we sold, the buyer had rising damp flagged on their survey. We were able to locate the source of the damp and it turned out it was because of some incorrect DIY that we had done ourselves - oops! We covered the cost of damp treatment and proofing and informed the neighbours, they had no problem with it, after all they do share the wall! It was a couple of days work but the disruption was to us not the buyers. Appreciate the situation is slightly different as we felt we needed to make the situation right and we also knew what caused the damp, but the work itself wasn’t that bad really.

Hi @Thebigpeanut could you tell me what work you had done as we are in a similar predicament and there seems to be loads of options and I want to make sure we pick the right one. Thankyou

Rising damp 1 foot up on the adjoined party wall can't really be any of those things you 'suggested' lol. That is the type of thing people with no experience quote after reading Facebook groups of amateur DIY reno 'builders'.

Our rental has the exact same thing OP, rising damp is water from the ground soil under the house traveling upwards through the mortar of the building, They key sign is its never more than 1 meter high and always the lowest level.

Roof leaks happen from the top down obviously and condensation happens high up on walls and ceilings or cold spots like external walls and windows. Penetrating damp can occur all over external wall floor to ceiling on all levels and is specific to the area(s) of damage.

OP Damp Rod should work, you can even install them yourself if needed (its re-plastering thats the hardest part of the job as all the salted plaster needs removing and replacing). They DO work, are pretty cheap but remember to wear gloves as the will suck all moisture out of your skin and burn you.

Yep. I use earthborn. Works a treat and great to put on ( though not as durable as Dulux, by definition).