Mysterious damp on kitchen floor and understairs

[Nasa89]

Hi,
I recently bought a house. Surveyor found some damp by the front door, he recommended a damp survey and the EA recommended a company who assessed the damp in all downstairs wall and treated the wall by the door. When we moved in we noticed dampness on the wall in the space under the stairs (salts on wall and tide mark) the floor is damp). One of the walls is external, the other wall goes to the kitchen (in that same corner in the kitchen is the stopcock). We were losing pressure in the gas heater so we got the plumber to try and find the leak, he opened the floor on that corner of the kitchen and it was all wet rubble and the old wet tiles (1930s semi). Finally the leak was upstairs, Completely unrelated problem.
What can I do to find out the source of the dampness? Could it be a small leak in the pipe coming from outside? We did not see any damp course when we excavated about 40cm deep in that corner.

Second, will the insurance cover finding the source of the damp? Do we have any case seekimg compensation from the damp surveyor (they came to the house and recognised they should have seen it and offered to repair it by... injecting the walls and putting new plaster. Guy was clueless about the cause of the damp 😞

I expect the water supply pipe is leaking under the floor.

Is the house over 30 years old? Quite likely.

Is it over 60 years old? Very likely.

Have you got a water meter?

Do you know where the outside stopcock us?

Do you know a young person with sharp, undamaged hearing?

Don't throw away any money on silicone injections or magic plaster.

The one thing you can be absolutely certain of, is that they will not repair leaking pipes or broken drains.

The house is 1930s, no water meter. The thing is, My Plumber had one of these sticks that you put at one end of the pipe and the other in your ear, and he couldn’t hear any leak.
I just remembered that under the lower part of the stairs, there is a wee door about 50cm high for storage, there is like a wood panel with a black plastic underneath against the bare brick wall, which seems damp at the bottom. What is it? Does this sound like the previous owner trying to hide the problem? This is a meter away from the kitchen and since the kitchen and the understairs are separated by a brickwall I’m afraid it could be all coming from the floor

good to hear the plumber already listened for a leak, that seemed the first thing to check. It could also be a neighbours pipe if you are in a semi or terrace; or a radiator pipe or hot-water pipe. If you have tanks in the lot this will show by contant dripping or running to ill the tank. Or it might be a waste pipe or sink leak. The plumber would probably have ound it i it was above ground. Do you think it could have been an appliance such as washing machine
please take some photos o the gulley or drain where the kitchen /waste pipe goes. sorry as you can see i spilt tea on my keyboard and some buttons not workin today

You seem to know a lot about damp. There was a tiny water leak on the dishwasher pipe (first picture on the left) we fixed it 2 months ago but it might have been going for years. However... I don’t thing the problem doesn’t come from here, the corner, where the mains pipes are, is soaking. Then is the understairs... the pipes on the left were fine and dry. The green pipe at the back has been disconnected for years (we just removed it). Plus the whole floor there is damp, on the right is the electricity meter, and the board is starting to soak too. The 3rd picture is the compartment at the bottom of the stairs. What is this board with a plastic put over the bare tiles??? Previous owner trying to dela with damp?

Electric meter and what’s behind the plastic... bricks are very damp.

This is why I am so worried, looks like coming from the floor, and under the stairs... do I need a new dpc???
Is that a proper job to cover the damp bricks with a board?

Bullet proof test for a incoming water main leak.

1. Make sure all taps are off.
2. Fill a pint glass with water under the kitchen tap
3. Raise the glass in the sink so the tap spout is actually submerged in the water
4. Turn off the water main at the external stopcock/water meter
5. Turn on the kitchen tap.

As the water is turned off at the mains, if you have a leak in the water main between the stopcock and the kitchen tap, the glass of water will start to empty as gravity siphons the water from the glass. If it stays full you can eliminate the water main as a suspect. The listening sticks are good but a small leak can be tricky to hear.

I can't make out your new pics very well, but there appears to be an old water pipe coming up through the ground, in a wet patch.

The assumption, until proved otherwise, is that the wet is due to a pipe leak.

I can't make out if there have been repairs or joints, or if there is a lead pipe or iron. Joints can weep, but a lead or iron pipe is likely to leak by age.

In one of your pics I think there are pipes running upwards in a duct, and there might be water dripping or running down inside the duct from a higher fault.

Tying dry kitchen roll tightly round pipes will show where they are wet.

Do you know where the outdoor stopock is?

Do you know a young person with good hearing?

I’m not at home at present but I will try your test :-)
It’s a lead pipe, I guess as old as the house! And that’s what I thought (that a small leak would be hard to heard with that device.
I don’t know where the Outdoor stopcock is, ill ask my husband.
I am not too old (Mid30s) & I believe I have still good hearing, what can I do?
O

Would the leak in that corner affect the floor all the way down to the beginning of the stairs?

Yes a mains water leak can cause that kind of issue.
Try the test, it may give you a quick answer.
If not, speak to a chartered surveyor not a damp company. They should be able to carry out a salt test on the plaster which can help confirm the source of the issue.

Ears:

put the young person in the kitchen (or by the suspect pipes) late at night when all is quiet. All taps, fridges, fans, radios, boiler, PCs are off.

Assistant goes outside, shuts door, closes and opens the outside stopcock repeatedly.

The noise of a leaking supply pipe is like faint white noise. You don't notice it until it stops and starts. Like when you're in an office block and the ventilation or aircon goes off.

on the other side of that wall, moss that seems a bit wet all the time (I must check on a sunny day).
So, since my plumber didn’t find any leak that day should I get a leak detector to source the leak or should I go straight to replace the lead pipe?
Can leak detectors find small leaks?

p.s.

An eight-year old, who can still hear bats, would be even better.

"on the other side of that wall,"

I spy a drain gulley.

Is it brown, glazed clay (like an old teapot)?

It's cracked and leaking. 1930's, they always are.

Your lead pipe probably is as well.

Where would the clay drain gulley be? Under the concrete where the pipe is draining?
Do I need to open that square manhole ( can’t think of the right word, baby induced sleep deprivation 😂)

Gullies commonly have a square iron grid that fits into the hole. The pipes discharge onto the grid to prevent leaves and other detritus causing a blockage.

The grid can be lifted out with a hooked implement for cleaning.

something like
this

a modern one may look like
this and often has a plastic grid that can be cut away allowing pipes to penetrate it.

The gulley may incorporate its own trap (bend) or it may be attached to a separate one.

Where they have broken, the ground often sinks (because it is washed away by the water) so the concrete round it may be sunken or cracked, or may have been buit up in a futile attempt to contain the leaking water.

JohnD2 says he once saw one that wasn't cracked. I never have

Trying to repair them will not work. They have to be dug out and replaced. Your local plumber may be able to verify if it is cracked, which is probably best before starting work, but plumbers are weedy fellows with petal-soft hands and he may be unsuited to heavy work. He may know a builder or labourer who can use a hammer and shovel, though.

looking again, I see the cover you mean. You can probably lift it with a spade. There is a special tool or this that fits in the keyholes.

Yours looks like steel so will not be as heavy as an iron one. As it is modern, you may be lucky and find someone has previously made a repair, or it might just be an new lid on an old chamber.

And here you see a typical break.

If you dig, you may find soapy or smelly water; red worms; and wild tomato plants, all of which confirm drain leaks.

Hi @Nasa89 looking at that photo you could have a few things going on here, or just one.

Having a lead main isn't ideal for health reasons, so it may be worth considering changing that anyway. At very least, digging down inside to investigate is an option.

Also, the manhole outside may be salt-glaze clay and as has been said, they can leak. That's not a certainty by any means, there's still plenty of perfectly fine clay drains around but worth a check. A builder/plumber can carry out a drain test to find out. This needs fixing if so as it can potentially affect the foundations.

Lastly, it looks like the ground slopes to the corner. So when it rains the surface water presumably goes in to the gulley? Check for big puddles in the corner after a shower, water may be pooling if the gulley is blocked and draining under the tarmac. Also, the gulley doesn't have a surround to stop water from the water pipe splashing, which isn't ideal.

This is often a bit like a detective story I'm afraid!

Thank you so much guys, there is so much knowledge here! I was trying to decide money wise whether to get a leak finder or an independent damp specialist, but now we can do a bit of detective work ourselves to find out a bit more.

We might change the lead pipe since we are at it.
Since this sounds expensive, is it worth to shop around for quotes? My plumber refused to give us a quote before as it is hard to estimate how long he would be searching for the leak and the extend of the damage. He is expensive but not sure if within the norm

Changing of the lead pipe is more of a builders job than a plumber. Most of the job is digging and making good, the pipe connections are quite simple.

It's quite disruptive to your floor and drive though, so take it step by step.

I have been away from home quite a lot but I got some updates. I got water tested for lead levels. The water company guy was quite relaxed saying that the levels would be low due to deposits of limescale, etc. Took a sample off the tap which had been on use all day and the results came back as 25!!! We have been having digestive symptoms since we moved in and I’m also worried about the baby (even though I only used this water to cook her food for a month until I noticed the lead pipe). The water company is now running some tests in the street. A leaking pipe is more likely to seep more lead into the water? I have been quoted 1.7k plus vat for the digging and replacement of 20mt of pipe. Other companies didnt even show up to give me a quote. This seems quite expensive, reading through other people’s experiences and considering living expenses are lower here than in England. Would getting a builder and a Plumber be cheaper?

If your price is from one of the Water Company's accredited contractors, they will tend to be expensive.

Any builder or labourer can dig a trench. So can a householder who knows how to grow beans or potatoes. It doesn't need to follow the same route as the old pipe. For example you may have access past the side of the house.

It is a bit harder to dig up a concrete drive or path than a garden or gravel, but builders do it every day of the week.

Typically a plumber would do the connections, and, if your outside stopcock or meter is under the pavement, you would probably have to pay the water co to do it. There are sometimes shortcuts.

Examine the water co's website carefully and quiz them to see if they have a Lead Replacement Scheme. For example they may give a subsidy, or free connecrtion, or will renew their part of the pipe (over the boundary) which makes it much easier to reconnect. I recommend at least 25mm blue plastic pipe, 32mm is preferable as your pipe is quite long and will give startlingly improved flow, especially if you get a large combi or an unvented cylinder in future. The difference in cost of the larger pipe is small, but you must get full-bore stopcocks (which are more expensive, and make sure the plumber doesn't "forget" to fit them). It is a hundred times more work to dig up and replace an inferior stopcock afterwards.

If you haven't already got a meter, you might ask them to fit one and connect to your new pipe at the same time (this may be free).

Try to find a long-established local plumber by personal recommendation, perhaps from a neighbour or in the parish magazine. If he is gnarled and wrinkly and has a roll-up behind his ear he has probably done hundreds and may know someone who can use a spade.

Advertising websites, where the trader pays to be listed and can remove unfavourable customer reviews, are not reliable personal recommendations, even if the website uses a name that suggests they are. Established and reputable traders don't use them.

p.s.

I understand that (some of?) the jug and tap water filters absorb the lead from the water, so might be a good move. But I'd contact the makers first and ask them to confirm it, there may be different types.
example