Damp identification help

[wedge69]

Hi,
New house, uncovering various things.
Could anyone help with this damp? Not sure if the pattern indicates what is causing it. Also not sure if it's historic or recent as we've only been here a couple of weeks.
The "damp" only appears to be on the end of the threshold, and not on either side of the wall.
Thanks

 

[JohnD]

how old is the house?

is that a concrete floor?

is there a kitchen or bathroom nearby?

please photograph the inside and the outside of the walls around it. All the way down to ground level.

any nearby radiators, pipes or other plumbing

and, on the outside, all the way up to the gutter, the paving, and around the doorframe and porch if there is one.

and the dpc in the walls.

where is the water stop-cock?

depending on age, I'd be thinking of a pipe leak under the floor, or water penetration round or above the doorframe.

I think that wall has recently been hacked off and replastered, probably to hide damp damage. There might be a pipe buried in the wall.

 

[wedge69]

That wall that you can see is a partition separating two rooms of what used to be an old brick outhouse.
The original outhouse was built in the 1700s, and was converted into living space in 2010. There obviously wasn't any damp proofing originally and unfortunately I don't have a record of what was done during the convertion.
Before we purchased we had the plumbing checked and no leaks were found. We also had a cctv drain inspection that spotted some issues we fixed, but not in that area of the house.

 

[JohnD]

when will the photos be ready?

tell us about the water pipes tomorrow.

 

[wedge69]

So here are photos of either side, and as you can see, there's no indication of damp.
Can you clarify what exterior photos you need? I'm just a bit confused as that patch is not near any external wall.
The stop cock is over by the washing machine.

 

[JohnD]

oh, I thought by threshold you meant an external door. I was thinking of dripping gutters, drain gullies, downpipes.

if it is nowhere near an external wall I expect it's a water pipe in the floor.

Where is the sink?

does the cupboard smell damp?

Are the radiator pipes in the floor?

Is it a concrete floor?

I can't see any marks on the wall with the socket. Is it plastered brick? or plasterboard?

 

[sxturbo]

Might be old damage, if it was more serious I would expect it to also be on either side of the wall.

It might be caused by condensation bin the kitchen over a number of years.

Also check to see if there are any pipes under the floor in that area

Also if it's as old as you say, it might have the wrong plaster on the walls, meaning the wall cannot breath as it should.

Rub it down back to bare plaster, prime it with zinsser bin and then paint over it, see how it goes. If it comes back will have to look into it a bit further

 

[wedge69]

Thanks for all your help so far.
There are no pipes within a meter or so of that area. The inside of the cupboard does not smell damp and I can't see anything untoward in the gap between the cupboard and the wall.
The floor is solid.
I think the water main does run under the floor somewhere in that area, but pre-purchase we did the 'water meter test that didn't show any leaks.
I've not looked hard enough yet to know if it's plaster or plaster board.
What was confusing me is that the patch is on only in the end, and not on either side.

 

[mrrusty]

My theory is it is a cold spot and condensation. I had a virtual identical spot in the kitchen in the last house. We had a fridge with base condenser next to it and the air circulation from the fridge caused condensation on the base of the wall nib (which at one time was an external wall). I bet there's a draught under the door.

 

[wedge69]

I know the previous owner used to have a tumble dryer, so maybe they contributed.
I keep an eye on it

 

[jeds]

Agree with mrrusty. Most likely long term condensation damage, possibly due to incorrect or contaminated plaster type, uninsulated wall junction with uninsulated floor, excessive moisture vapour, poor ventilation, etc. Numerous possible reasons.