Advice needed for damp floor problem please.....

[valleyboy]

Evening All,

This is my first post but I am a regular lurker here, usually find what I'm looking for regarding DIY jobs but I've got a slightly bigger problem, hope you can advise the best course of action. May be a bit long winded, sorry, please bare with me........

I live in a mid-terrace house built approximately 1890 I think. Moved in about eight years ago. Extensive work was done to treat damp at the time (hack off walls, damp proof injection treatment in walls, re-render and plaster etc.).

Downstairs floor is concrete throughout. I have a small hallway between the front door and the stairs with an adjoining wall one side (brick), and a brick will the other side that divides the living room/hall.

Just recently noticed this (against adjoining wall)........

and this (against living room wall).......

These patches continue here and there along the walls either side of the stairs.

I've had a builder have a look. He said possibly leaky pipe under the floor, or possibly no DPM. He suggested I get a damp proofer to diagnose the problem.

The damp proofer came today and his meter says that the floor is damp (even in the places that look dry). What are your thoughts on this? Can you let me have some suggestions on what you think is involved to rectify the problem?

Cheers.

 

[valleyboy]

Would somebody please let me know if they can see the images that I've tried to post? I can't view them myself. Don't know if I have done it properly. Cheers.

 

[noseall]

i'm not getting an image, just x

 

[valleyboy]

Thanks.

How hard can it be? OK, try these....

Adjoining wall.....

Untitled

• valleyboy
• 27 May 2008
• 1

Living room (interior) wall......

Untitled

• valleyboy
• 27 May 2008
• 1

Thanks again.

 

[^woody^]

The damp proofer has not exactly diagnosed the probelm if he has just said "the floor is damp"

I would also hazard a guess that he has placed an electronic meter on the floor and come to this amazing conclusion?

You do appear to have a damp issue and it's relatively localised spot may be a burst - but are there pipes under this area?

If it is a burst it will remain damp from now on, if its a defective or lack of DPM, then it may come and go

 

[valleyboy]

Thanks for the reply.

Yes there are pipes under this area. A fresh water pipe from the stop tap outside the front door I believe.

So, looks like I need to dig the floor up to get a proper diagnosis then? Can anyone suggest a method of pinpointing an underground leak from above the surface? If it is a pipe leaking, I take it that it would be buried above the level of a DPM?

 

[chessspy]

Hi, Valleyboy,
It certainly could be a perforated water pipe, I live in a similar house and same period, and the water feed runs down the hall under the floor.
In my place the floors are wood over the natural chalk sub floor, and it depends on wether your concrete floors are original or later, in any event the Victorian builders weren't much on DPMs.
I've tried to think if there are any practical ways to detect a leak by sound, or by maybe turning the supply off etc but nothing comes up as possible
If you were going on hols for a few days, if you had a stop cock by the front door (under the doormat well often) then it just might be possible to try leaving the supply off for a few days, but even then the water in the system would feed back, mostly the stopper is in the street feeding 2 or 3 adjacent houses and the stop for yours may be in the 'washouse'/kitchen.