Would you buy a house with damp issues that required expensive remedial work?

[SR193]

In the process of buying a 1930s semi-detached home. The house appeared to be in good condition, recently renovated. Survey indicated damp in 2 ground level external walls.

Called in a independent damp specialist who identified the cause. The house is a solid brick construction with no cavity wall, which means the walls must be allowed to breathe.

1. The house has an external render made of impermeable cement which is trapping moisture between the wall and render.
2. The render comes all the way to the ground and bridges the damp proof course.
3. The ground level at the rear (patio) is raised above the damp proof course.

The suggested course of action is to remove and replace the render (£15,000), and lower the ground level (£2500-£3000).

Other issues with the house/vendors:

1. Vendors initially lied on the property information form that no construction work was done to the property - it has a 2 storey extension and had an internal load-bearing wall removed!
2. No building regulation certificate present for the extension - eventually, they agreed to get this, and said an inspection was done, but we are yet to see the certificate.
3. No fensa certificate or equivalent
4. No boiler installation certifiate (installed in 2016) and no service history.
5. Mould in the hot water cylinder (installed in 2016) cupboard from poor ventilation.

Should I consider negotiating the price or is it time to pull-out? Don't have much confidence in the vendors and worried about spending £18K on remedial work only to have damp re-appear. There's also the possiblitlty of unknown underlying structural damage to the floor.

Does anyone have experience of buying a house with damp issues? Were you able to solve the problem or were you left with ongoing issues and expenses?

Sorry for the long message, just wanted to try and cover all the details in one go.

That would scare me so I wouldn’t proceed, tbh.

We had damp in one small room. It cost over £3,000 to fix and, on rainy days, I swear I can still smell damp -despite a new DPC and new insulated plasterboard and plaster.
I’m convinced there is damp between the bricks and the plasterboard that just isn’t showing through the plaster due to the thick polystyrene insulation layer so it is possible you could have further issues.

I wouldn’t go ahead with the amount of issues you’ve listed tbh, it sounds like a money pit. unless there was a significant reduction in price to cover all the work, plus an additional contingency, I’d walk.

I wouldn't walk away from this one - I'd run. Why buy trouble?

Never.

The extension concerns me far more than the damp. Lying about moving a load bearing wall is pretty outrageous too.

So they have already been proven to be liars. So what else hasn't the survey uncovered?

Nah.

No builder worth his salt would bridge a dpc.
It might cost 18k to fix, what if it costs 30k?

Personally I wouldn’t buy a single skin solid wall house. Cavities were invented for a reason, warmth and damp.
Add on the other issues and it’s getting very risky.
As PP says, why buy someone else’s problems?

I’m not afraid of negative surveys but everything you’ve listed speaks about a house tampered with by cowboy builders.

render past the DPC? Only an idiot would install it.

raising ground level past the DPC? Only an idiot would do it.

internal load bearing wall removed and no building control certificate? Just nuts.

almost certainly this won’t be all you discover. I’d avoid…

Thank you so much to all the posters here. Your personal experiences and advice has helped to confirm my doubts. Wasn't sure if I was being overly cautious as I am a risk averse person, which is why I posted - a first for me. But seems like a lot of people here have more knowledge and sense than my conveyancers! Thanks again, going to pull out of the purchase!

I think you're doing the right thing OP.
We live in a solid wall rendered 1930s house. Don't have any problems with damp as we have lots of air bricks & render doesn't breech the DPC. Love its character & amazing location but I'm already starting to dread the arrival of winter as it's absolutely bloody freezing & costs a fortune to heat. Wouldn't buy it again on this basis alone.

Can''t they just remove the bottom bit of the render? That's the usual problem- render down to the ground when it shouldn't be.
Ground levels also are often too high, you'd have to have the patio relaid.
The removed wall, lack of certificates in general, and a vendor not being truthful would be red flags for me though. I'd pass on this one, I think.

Thanks for sharing your experience. I hadn't really thought about the heating side of things with single wall homes. Will bear that in mind.

I asked the damp specialist that exact question, whether we could just hack off the lower half of the render. He said it should help solve the damp issue on the ground level walls and we could do that as a short-term fix, but in the long run, moisture would be trapped between the impermeable cement render and wall, causing long term structural damage. He said a permeable lime-based render is best for old properties with no cavity; it allows miosture to freely evaporate.

To be fair, if it’s waterproof render, then the moisture can only come from within the house.
If you keep it adequately/normally ventilated, I can’t see a point where it would get that bad/much water in the walls as to cause ‘structural damage’. By that I presume he means popping the render off.

Doesn’t alter my opinion on this house though!

Yes agree. Something just doesn't feel quite right.

No I would walk away

I ws thinking just the bit below the DPC, because I had forgotten it's different with solid brick, my bad. I'm sure your bloke is right. I'm having to repoint the cement mortar here with lime even though we do have a cavity (Our cement render starts at abut 1m high so it's just pointed brick below that).
I think this one is one to walk away from, I'm afraid.