Hello
I am having a very longstanding battle with wall/floor junction dampness and thought i had nailed it recently but is now back. All floors are concrete and ground floor and in the next room (the bathroom) the soil pipe had been leaking for sometime into the foundations. An outside gully was also open to the foundations so daily showers and sink usage were also going to ground, along with the toilet flushing. It is the main bathroom.
To replace the soil pipe and outside gully in plastic, the builders basically escavated underneath the foundation so at one point you could see underneath the bathroom floor slab. They said it was absolutely sopping under there. They also noted that the foundation was practically at ground level, so the bottom of the cavity, even if it was clear, is practically level with the exterior ground level.
What was odd (good), was that in the next room where the wall/floor junction damp is, there was an almost immediate improvement in air quality, an odd background smell disappeared, and best of all the damp seemed to improve almost overnight.
Now that the work has been completed, as of about 3 weeks ago, the "damp" is coming back.
If i put a business card down between the floor slab and bottom row of bricks, it comes out wet. Yet when i inspected inside the cavities they appeared to be dry (camera).
There is an old lead incoming pipe in a different room but no real signs of damp right by there (in case it was still leaking for example). When i get time i'll try and locate it in garden and flatten it but i discussed with waterboard and they said it was all dead.
The only other thing that has changed is outside temperature, so havent ruled out condensation as a contributory factor other than when we had the dry spell during the summer the damp was at its worst, so it can't be the only factor.
At my wits end with this and wondered if some of the above might ring a bell with someone, as to where to look next. The floor slab itself is dry btw, as are the backs (inside the cavity) of the bricks - its almost as if the damp is coming up specifically along the wall/floor junction.
Could moisture be penetrating horizontally across the shallow cavity bottom, and then selectively appearing internally depending on temperature, and/or pourosity of the brickwork/pointing ? Black ash mortar btw. Feels wet to touch in places, bone dry (grey) in others).
Thanks
Mike
I am having a very longstanding battle with wall/floor junction dampness and thought i had nailed it recently but is now back. All floors are concrete and ground floor and in the next room (the bathroom) the soil pipe had been leaking for sometime into the foundations. An outside gully was also open to the foundations so daily showers and sink usage were also going to ground, along with the toilet flushing. It is the main bathroom.
To replace the soil pipe and outside gully in plastic, the builders basically escavated underneath the foundation so at one point you could see underneath the bathroom floor slab. They said it was absolutely sopping under there. They also noted that the foundation was practically at ground level, so the bottom of the cavity, even if it was clear, is practically level with the exterior ground level.
What was odd (good), was that in the next room where the wall/floor junction damp is, there was an almost immediate improvement in air quality, an odd background smell disappeared, and best of all the damp seemed to improve almost overnight.
Now that the work has been completed, as of about 3 weeks ago, the "damp" is coming back.
If i put a business card down between the floor slab and bottom row of bricks, it comes out wet. Yet when i inspected inside the cavities they appeared to be dry (camera).
There is an old lead incoming pipe in a different room but no real signs of damp right by there (in case it was still leaking for example). When i get time i'll try and locate it in garden and flatten it but i discussed with waterboard and they said it was all dead.
The only other thing that has changed is outside temperature, so havent ruled out condensation as a contributory factor other than when we had the dry spell during the summer the damp was at its worst, so it can't be the only factor.
At my wits end with this and wondered if some of the above might ring a bell with someone, as to where to look next. The floor slab itself is dry btw, as are the backs (inside the cavity) of the bricks - its almost as if the damp is coming up specifically along the wall/floor junction.
Could moisture be penetrating horizontally across the shallow cavity bottom, and then selectively appearing internally depending on temperature, and/or pourosity of the brickwork/pointing ? Black ash mortar btw. Feels wet to touch in places, bone dry (grey) in others).
Thanks
Mike
