Help! What is causing this blown plaster?!

steviecooke

Hi everyone, 

We have a problem with some water or moisture getting in from somewhere and blowing the plaster in our wall. It's not a lot of water, as this has been gradually getting worse over the course of a year (you can see the patch job where we did a quick repair on some blown plaster to see if something had fixed the water issue - turns out it hadn't! You can see the brown water stain on top of the patch job where it continued to come through).

The only two remaining options are: 

1. Something getting in from the wall on the other side? We share this with a scrap yard and they have security lights in the wall, but we've checked and can't see any evidence of water anywhere. We will check again, but nothing seems to correlate with where the problem is on the inside of the wall. 

2. Could it be anything to do with this mysterious pipe we found under the floorboard (second pic)? No idea what it is, so any help identifying what it is would be great! And how likely is it that the pipe is also in the wall? The blown plaster leads from the pipe under the landing floorboard, down to where the water main is.

3. Could it just be general damp moisture rather than any leak? Seems like it's too big a problem to just be from damp/general moisture?

It's driving me mad, and we just want to fix the plaster, but can't work out where the issue is coming from! So any help much appreciated!

FreeBear

Are you sure it is a water pipe - Is it possibly an old gas pipe ?

Spies

That's a water pipe, you wouldn't have a threaded section on a gas pipe.

FreeBear

Spies said: That's a water pipe, you wouldn't have a threaded section on a gas pipe.

Malleable iron pipes & fittings are all threaded - These would/could be used for gas.

NSG666

You might as well rake the plaster out to take a look - pipes were buried in the walls in the past

plumb1_2

That’s a old gas pipe

Norman_Castle

Is it a solid or cavity wall? I've got a solid wall which had a small area of damaged render which allowed water through damaging the plaster. How closely have you checked where the lights are fitted?

morhen

I would say it's an old iron gas pipe, looks exactly like the ones I have just had removed.  When there is water getting into a wall, I was always told to check the gutters, roof and any drain pipes etc first.  Have you looked at any of theses yet?

Tranboy

I second the above. I've had a damp wall recently that was down to a leaking plastic waste water pipe on the outside wall only spotted by a neighbour.

steviecooke

Thanks for the advice everyone! 

There aren't any gutters or anything on that wall, and the roof on that side was fixed a couple of years ago. So I suspect it must be a bit of render or that the moisture is somehow getting through where the lights are, as it is a solid brick wall. 

I will check again for any signs of water getting in - do you think it's best to check on a day when it has recently rained for the best chance of spotting it? And how would we try and seal up any areas around the light fittings that could be letting water in? 

It's legally our wall, so I could ask them to remove everything - but would rather just try and fix it and maintain the peace!

FreeBear

Water can track some distance both horizontally and vertically. So you need to examine the whole wall for cracks in the render.