What is causing this ☹️

[Gizzy1990]

Hi all, moving into a new home and I have been decorating it and the paint is just not drying out here. When we lifted the underlay, it was wet underneath. And the concrete still looks wet days later, the two big walls are internal walls with a stairs and and utility room the other side and the picture with a small bit with the radio in is an external wall which I can kind of understand the damp there! The previous owner had a car accident and had loss of bladder control for a year so used to have accidents and the carpet was cleaned a lot and then this house was left for 18 months empty with no heating on. Could this have made it worse? I’m thinking there could possibly be a leak somewhere but can’t see where so would have to be underground or in the wall Help! Bringing a heater and dehumidifier up later on to see if it would make a difference but looking at the floor, it makes me anxious that there is a bigger problem somewhere. Thanks in advance for your replies! X

[dewaltdisney]

First thing to check is washing machine feeds in the utility. I have seen localised damp issues like this quite a few times were the culprit was a steady drip from a loose washing machine feed. You would be amazed at the spread and saturation over a long period of steady drips. Now this issue may have been resolved in the move withhis old machine gone but have a good look at all the plumbing and wastes in the utility.

I am not discounting a damp course issue but he pattern does not suggest this as a reason to me.

DWD

[Dave54]

Agree with Walt about the leaking WM connector.
Or it could possibly be condensation. Floor's cold, and it draws heat out of the bottom of the wall. You put heat on, in a damp house, the air collects moisture and you'll get condensation on the coldest places.

What's the soil level doing outside? Any decking out there?

[wine~o]

As per DWD's post, check all connections, even a tiny weep can cause the issues you have over time, I had a tiny weep on a bathroom I fitted some years ago (Isolation valve, drip formed about every 20 minutes so wasn't picked up immediately) 3 months later got called back to investigate damp...

[Gizzy1990]

Thanks all, the other side in the utility is just cupboards and the washer and boiler is on the opposite wall but I did look under cupboards today and there is copper pipe running under there for possibly the heating, can’t see no obvious signs of a leak but think I’m going to remove the cupboards in utility for a better look. Used a dehumidifier in there all today and the floor and wall dried up lovely, just unsure if it will stay like that now. No decking at all. It’s all concrete outside. Checked outside by the window and can’t see anywhere possible that water could get in. There’s not been a washer or anything in the house for 18 months but it’s a very cold house anyway and especially with no heating on. I’m thinking maybe as we are there now with heat on that it could possibly be condensation. Fingers crossed it don’t come back but I won’t be laying carpet until I know it’s sorted. Thanks all xx

[Gadget]

This is how it looks after dehumidifier xx

Really?..

[sammy.se]

A contributor to damp problems I had included condensation on the unlagged cold water pipe running under the floorboards.

Could you draw a diagram showing us where your pipes run, and what is on your external wall in terms of guttering, gulley etc?

[sammy.se]

Also, what's the height of the outside ground, relative to the inside floor? and I assume those floors are all solid concrete? or something else?

[wes56]

You appear to have rising damp issues.
Remove the length of skirting below the DSS outlet, and examine the back of the skirting, and look for the edge of any membrane (DPM)
thats been flopped up the wall behind the skirting.