Damp or leak?!

[xplosiv]

Hi all,

I've already posted about this issue in the building forum, but I have a couple questions specific to plumbing.

Basically, I've recently noticed some damp patches in my hallway on the interior wall (the living room is the other side) just above the skirting - one patch is near-ish the front door and the other further along by the stairs. I don't know how long the damp has been there, but I'm sure I'd have noticed them had they been there for weeks/months. My initial thought was that it's rising damp; however, someone has alternatively suggested that it could possibly be caused by a leak in the water pipe (i believe the water comes into the house from just outside the front door - I live in a victorian mid-terrace).

My reservation with the leaky pipe theory is that there's a gap between the two areas of dampness along the hallway - rather than one large damp area - so unless there's more than one leak in the pipe I'm uncertain why this would be the case.

I'm planning to lift up the laminate flooring to see if that gives any clues. I have a feeling the water pipe is under concrete, so if there's a leak I guess there'd be a fair amount of water/moisture on the surface? Is there any way of telling whether it's a leak or rising damp? Would a plumber be able to tell me if there's a leak in a pipe beneath concrete?

I just really need to know the cause of the damp so I know what action to take.

Thanks for your help.

 

[spacethegas]

from what you say you have a solid floor (not floorboards) & suspect the incoming water service is possibly leaking.

if you have an external water meter you can shut off your stopcock before you go to work in the morning take a meter reading & check it when you return.

another method is to shut the stopcock in the road before you go to work.
when you return damp your finger & hold it on the kitchen tap outlet, turn the tap on. if you feel any suction you have a leak.

there are various other methods based on the above.

also a trained ear can hear it.