Cold water pipe causing damp

[Hairy Ape]

We live in an old red brick terrace and have damp issues.

The mains cold water pipe rises from the floor under the stairs and travels horizontally through the wall to the kitchen. Unfortunately we get a lot of salts coming out of the wall and bubbling.

I Would guess it's caused by the condensation from the vold water pipe. Is there any way to prevent the problem?

[OchAye]

It can't be condensation from the pipe.

The condensation (vapour/steam rather) is in the air inside the house which then finds the coldest parts it can find and condenses and becomes water. Humm, that was the part I do understand. The cure is a different problem

Alkali resisting primer (paint) is meant to help issues with efflorescence but it can't do much about steam condensing on a particular spot which will affect most paints you put there. Does the house have good ventilation (those things on double glazed windows that are meant to open)? If you eliminate the steam the problem may sort itself out.

If it is efflorescence then alkali resisting primer and you will have to ask at the painting and decorating forum if you should paint all the wall or just an area sufficiently wider than where the pipe is. If not, there are some wallpapers that are supposed to offer some thermal insulation but that would mean wallpapering all the wall(s) where the problem is :-(

[Hairy Ape]

I've attached a photo to show what I'm talking about. You can see how the damp tracks up the wall from the pipe and is affecting other areas. The pipe is the main incoming water supply.

Should I still be aiming to follow the advi e you kindly offered OchAye?

[Kev888]

I'm not as experienced as OchAye in this kind of thing, so defer to him if he disagrees. But if it is condensation then the moisture from the air would condense due to the cold wall (mostly) around the pipe.

It could then seep into the wall and spread somewhat if the surface paint etc was fairly porous. But if I'm interpreting the photo correctly, with the dark stain spreading upwards and also across from the pipe (plus perhaps the blotches and apparent tide marks further up the wall), I'd be surprised to see it go quite that far unless it was really very porous, and you have a lot of steam and/or pretty poor ventilation & heating.

If not, I wonder if there may be another cause of the damp, such as a pipe leak or rising damp in the corner (it does look a bit like the damp is getting out of the corners, rather than generally in). TBH it doesn't look like the most securely fixed and cared-for pipe. On this side at least, the pipe runs down from the wall so condensation won't run along it into the wall, it may be different on the other side though.

[OchAye]

I've attached a photo to show what I'm talking about. You can see how the damp tracks up the wall from the pipe and is affecting other areas. The pipe is the main incoming water supply.

Should I still be aiming to follow the advi e you kindly offered OchAye?

No, you should not follow my advice!!! In fact it is completely irrelevant. I imagined what you wrote

The mains cold water pipe rises from the floor under the stairs and travels horizontally through the wall to the kitchen. Unfortunately we get a lot of salts coming out of the wall and bubbling.

was a pipe buried in the wall, somewhere high up, not a visible pipe round the skirting board. Whatever I wrote is not a solution. The photograph is completely different stuff.

I agree with Kev's feeling and I would add this is most likely rising damp. If it is the pipe + condensation you would be able to pick up water droplets on it as the pipe is exposed. It is too much dampness for ordinary household steam condensing on a pipe unless you are drying all your washing in the house or similar stuff :-(

Soooorrrry :-(

[Hairy Ape]

Hi

Thanks for the reply. You're right, it's not the best pipe. Pops up out of the floor about a foot away from that corner. Not too much we can do with it, short of turning off the water in the street and ripping up the floorboards to replace it.

The wall the the left is internal and backs onto the kitchen, to the right, are the neighbours.

The house shows signs of having had a DPC but I don't know if this extends to party walls or not.

Sounds like I might need to get a damp expert on to look at it. Was hoping it wouldn't come to that.

OchAye no need to apologise. If I'd put the pic up to start with, that would've helped. I just appreciate any advice.

What are your thoughts on rising damp? I know there are big arguments about it in terms of what people say causes it (if it exists)

[Kev888]

I edited my last post a tad before realising new ones were being added, so maybe look back at it. But anyway, I had the benefit of the photo when I posted so can claim no special powers. I still wouldn't like to guarantee that it absolutely cannot be down to condensation, but from the photo, that seems a bit unlikely.

Whilst IMO rising damp is often over-stated, I believe that moisture does rise in limited circumstances; if there is a source of it and no barrier to prevent that. Whether in this case it would be rising from the floor, next door, or a small crack in the pipe I've no idea unfortunately.

Personally I would start to investigate by carefully excavating the plaster and wall just a little around the pipe to see if any damage may be found with that; it does look rather strained and the damp appears to originate in that area. Though if this pipe is before the stop-cock it is worth making sure you can turn the water off outside the property just in case there is a crack which the masonry is plugging. (If I misunderstood and it is after the stop-cock then check that it still works).