Damp/leak in stone cottage?

[dampcottage]

I have seen some brilliant answers on here, especially from @pigletjohn (long time watcher!)so thought it would be worth posting as we really aren’t sure what to do! Hoping someone might be able to shed some insight or advise us on dealing with a damp problem we have been having in one room of our house. The main part of the cottage itself is over 100 years old and as such probably doesn’t have any form of modern damp proofing. I’m not entirely sure of the building material but the walls are exceptionally thick (stone) with deep windowsills etc. We are based in Northern Ireland.

The wall in this damp corner is wet to touch. We have lived here over 5 years and this has been a problem for us probably for a couple of years now (not during the summer) and we have been searching for advice from various sources who have all advised different solutions. Eg. Internal damp proofing, scoping the drains, external damp proofing, new drains. We haven’t really done anything major as we don’t know what to do!

The area where the problem is occurring is probably the the lowest part of the house. As you can see from the external photographs water naturally runs towards a drain at this corner off the wall. I've tried to mark on the photographs the direction of the drainage etc. I’ve also tried putting an endoscope down the drain (which is not in any way blocked) to inspect for any damage. From what I could see there were no cracks or areas of concern anywhere close to that corner (or anywhere I could see). To the best of my knowledge we don’t have any cracked roof tiles that would let water in that way.

One thing to be aware off is that the land around that side of the house is very wet and boggy. I don’t know if this has any relevance but thought it worth mentioning.

We are suspicious of the downpipe directly outside the wall where the problem is. But as I've said I don't see anything that makes me certain it is the cause of the issue.

Our current heating pipes run through the attic so aren’t under the floor. Could it be an old pipe leaking?

Could anyone advise what type of company we should be contacting to work out what is going on?

the shape of the damp patch suggests that the source of water is at, or very close to, the corner.

I observe a downpipe at that very point.

look at the gutter and pipe during rain to see if water is excaping above ground

but I think more likely the gulley and drain (if any) in the ground are broken and leaking. Most likely there is (was) a salt-glazed clay gulley and drain, which IME are always cracked, broken and leaking. Get out your garden trowel and spade and start digging.

The glazed clayware is mid to dark brown, like an old teapot.

If broken, that would also explain the wet soil.

Do not allow anybody who sells silicone injections near your home.

A builder can dig it out and fit new. When you have found the leak, carry on digging to expose more of the pipe, there may be another leak. They usually break at bends and joints. Modern plastic replacements do not break so easily and can bend a little. Look at the wall in the ground near the break. Lime mortar washes away near leaks. An experienced local builder will be familiar with the construction of your wall. Round here it's brick, and I hose the mud out of the joints and repack with cement mortar, usually old houses are built with lime mortar but I don't know if it will set if constantly wet with no air. Underground, it does not need to "breathe"

Once it has been repaired, the wall will start to dry. It will take at least a year. If your flooring has been laid on an old concrete floor, with no DPM, the floor will be wet so you ought to take up the flooring so you can see what the damage is, and let it dry out. if the plaster is modern gypsum you can hack it off and dry it with an ordsinary fan (not a fan heater). If lime it may dry out and recover. Lime is preferable on an old stone building. No point in doing anything until you have rectified the source of water.

If, when you dig it out, the water is not coming from the downpipe and drain, you can think about a water pipe leak or a French Drain or other options. But not yet.

An original clay gulley looks something like this. May be darker brown depending on local clay. Stands around 18" tall and would be rather heavy if if one piece, but I have never found one still in one piece.

It will break at the top bend, the bottom bend, and the socket where it connects to the pipe. Sometimes it also breaks under the square grille. If a new plastic one has already been fitted, it is probably leaking at the broken joint into the pipe, which will have been smothered in mortar or concrete in a valiant but futile attempt to repair it.

Nominating @pigletjohn for some sort of OBE type award.
He's been around as long as I've been on MN, which is a long time, and such a treasure.

I totally agree @justforthisnow I am very very grateful for the help! It has been suggested before to us the problem may be with clay pipes. The only this is this area around the house (and down pipe) is actually concrete I assume we would just get a builder to dig this up? To have a look? Sorry the wet land i referred to originally is beyond the concrete surrounding the house

Hope you get sorted

well start by looking at the downpipe, gutter and roof in case water is spilling down the wall. You seem to have a plastic dry verge on the edge of the roof, which is unusual in an old building. See if water runs off it.

Just throwing this in to help - though I know nothing!

We experienced something similar recently, though problem area, some distance from rain water down pipe(s).
Block paved and gravel around the area in question.
Long, long story short, we had drains CCTV'd by local drain company (and some others! - don't ask), and they discovered that the underground drain in question, met another rainwater drain at a Y-shaped joint and the joint had broken and collapsed. Water seeping nicely under block paved area.

We also needed other cracked pipework repaired at the back of the house and this was able to be done in situ without digging up anything.

I'd also like to add that my clay, glazed, kitchen sink gulley, circa 1900 is intact and functioning - for now!

Thank you so much for the replies on this! We will recheck the down pipe ( though we have checked before and the water seems to be moving through with no leaks) and then I think get someone experienced to have a look at the drains/ gulley and take it from there.