Help! Damp on the wall

starkiwi26

Dear all fellow members,
Merry Christmas and Happy New Year!

I have a problem which had been troubled me for sometimes. I stay in a Victorian house, the wall is brick wall. I attach my house plan as below, I recently noticed damp and mould on the wall at the highlighted area in the plan.



You can see from my floor plan, the damp area is actually below the shower cubicle. Therefore I suspect it is due to water leak at shower cubicle. To prove this, I had been showering at my gym for past 2 weeks, yet I still notice the damp on the wall.

I turned off all tap overnight (about 8 hours), and monitored the water meter, the water meter move 1 unit (or 0.1 unit, red colour number). Do this mean water leaking?


I monitored the external wall also, all surrounding wall is dry, but the external wall at that area is constantly wet. But it rain a lot, I am not sure the wet wall caused by rain water or leak from inside. Any method to check this?

Full resolution photo here: https://i.imgur.com/pfvQsPK.jpg

Anyway, I narrow down to 2 possible causes
a) penetration damp from external wall
b) Is it possible plumbing leak inside the wall (it is brick wall (Victorian house)? There is a cold water plumbing built in the wall to supply the electric shower unit at the shower cubicle.

Fellow MSE members, I am helpless.
Have been worrying this problem all my Christmas...
a) Please share your idea what is causing the damp problem at my house?
b) if this is a penetration damp, and I can always apply a coat of "Water Repellent" to resolve this. But, it had been always raining, and I never see that part of wall dry, which prevent me to apply this...
c) Do this cover in my insurance?
I have house insurance and also Homeserve plumbing insurance (75p/month). I bought the Homeserve insurance last year because it is so cheap, though I already have home insurance coverage. If to claim the insurance, I prefer to claim homeserve because my home insurance has high excess.

FreeBear

starkiwi26 wrote: »

Dear all fellow members,
Merry Christmas and Happy New Year!

I have a problem which had been troubled me for sometimes. I stay in a Victorian house, the wall is brick wall. I attach my house plan as below, I recently noticed damp and mould on the wall at the highlighted area in the plan.



You can see from my floor plan, the damp area is actually below the shower cubicle. Therefore I suspect it is due to water leak at shower cubicle. To prove this, I had been showering at my gym for past 2 weeks, yet I still notice the damp on the wall.

I turned off all tap overnight (about 8 hours), and monitored the water meter, the water meter move 1 unit (or 0.1 unit, red colour number). Do this mean water leaking?


I monitored the external wall also, all surrounding wall is dry, but the external wall at that area is constantly wet. But it rain a lot, I am not sure the wet wall caused by rain water or leak from inside. Any method to check this?

Full resolution photo here: https://i.imgur.com/pfvQsPK.jpg

Anyway, I narrow down to 2 possible causes
a) penetration damp from external wall
b) Is it possible plumbing leak inside the wall (it is brick wall (Victorian house)? There is a cold water plumbing built in the wall to supply the electric shower unit at the shower cubicle.

Fellow MSE members, I am helpless.
Have been worrying this problem all my Christmas...
a) Please share your idea what is causing the damp problem at my house?
b) if this is a penetration damp, and I can always apply a coat of "Water Repellent" to resolve this. But, it had been always raining, and I never see that part of wall dry, which prevent me to apply this...
c) Do this cover in my insurance?
I have house insurance and also Homeserve plumbing insurance (75p/month). I bought the Homeserve insurance last year because it is so cheap, though I already have home insurance coverage. If to claim the insurance, I prefer to claim homeserve because my home insurance has high excess.

First off - Will the insurance cover it ?
Probably not. They may well dismiss it as a lack of maintenance. You said the water meter is moving 0.1 unit overnight - This would suggest a small leak somewhere in the cold water plumbing...

If you can gain access to the pipe feeding the shower, it may be possible to fit an isolation valve and do a pressure test - If there is a leak, then the test will confirm it and you can isolate the pipe before conducting a repair.

A water repellent will not cure the damp wall and is more likely to trap moisture in the brickwork. This could eventually lead to the bricks spalling when the frosts come and give you an even bigger problem. Solid brick walls will take a long, long time to dry out (typically, one month for each inch of thickness, so around eight months for your wall).

starkiwi26

Just checked my insurance policy and found below
So, the insurance will identify where is the leak, up to £10k (minus 1k excess)
After the leak is identified, will the insurance fix the problem?

Davesnave

This insurance will probably not help you.

Firstly, you have to pay the first £500 of an investigation unless you have altered the basic policy to cover that as well. It's likely that finding the cause will cost less than £500.

Secondly, it doesn't cover damage by a gradual leak, which is what this is.

Thirdly, it doesn't cover repair to the pipe the water escaped from, which is what you want to have done.

Sorry!

starkiwi26

Thanks, this is fair point.
To repair myself, who shall I turn to? plumbing? handyman? damp proof specialist?
Appreciate if anyone can provide me approximate cost because I have limited budget after Christmas festival.
My location is at Staffordshire, if any member happen to be just nearby.

Jackmydad

It's only a guess, but assuming a solid wall, from the height the damp is above the waste on the wall, I'd be looking at the pipe up to the shower. Possibly the joint at the shower.
As FreeBear says, get a pressure test done on the pipe if possible. Otherwise it's a visual inspection, which will mean removing tiles, etc.
I hate to say this, but I'd want to have a look under the floorboards below the shower as well.
You don't want damp in there that is just left.

FreeBear

starkiwi26 wrote: »

To repair myself, who shall I turn to? plumbing? handyman? damp proof specialist?

You certainly do not want a "damp proof specialist" - They will try to sell you all sorts of inappropriate snake oils such as waterproof plaster.

A plumber will only want to do pipework, but as the pipes are buried in the wall, additional work would be required. A handyman with good plumbing skills would be the ideal person, even better if he can do plastering & tiling to a good standard.

starkiwi26

I am checking at mybuilder website, let's see if any traders can do the pressure test for me.
The shower is electric shower, it is about 1.5 meter from the waste water drain. from the external wet wall location, I suspect the leak is between the electric shower and waste water drain.
If not, after this festival (Christmas and new year), I will turn off the main stop tap for the water supply for 1 week, see if there is still any damp on the wall. Unfortunately, I cannot find the stop tap for first floor, if not I can stop the water supply to bathroom, but still have water supply at kitchen.
Please see photo below, how do I take the look under the floorboards below the shower? cut the ceiling of the ground floor?

starkiwi26

The wall on top of the shower had been like below for sometimes, I always thought the wall and ceiling were caused by the condensation and vapour when showering.


I pop my finger for checking the wall, and accidentally push through it, making a small finger hole as photo below. and it is wet inside. From the external wall photo, the external wall didnt show wet around the extractor fan. Now, I am even more confuse with the problem and root cause...

starkiwi26

one lovely builder came and checked, he told my house is Victorian house, didnt have the membrane under the roof, which cause the problem. It cost £2k to add the membrane under the roof.
It is year end, £2k is a lot to me, what shall I do? :(:(

Furts

starkiwi26 wrote: »

one lovely builder came and checked, he told my house is Victorian house, didnt have the membrane under the roof, which cause the problem. It cost £2k to add the membrane under the roof.
It is year end, £2k is a lot to me, what shall I do? :(:(

This sounds like nonsense to me. My reaction would be to say bo--ocks to the builder, then tell him to p-ss off.


Think it through ... if rain is getting into your roof space then clearly it is a fault with your roof covering, like a hole in the tiles, and this has nothing to do with a membrane not being in place. Then think a little further ... how can a hole in the roof tiles cause efflorescence (white furriness) on a small patch of your external wall? How can a hole in a roof tile cause suspected wet under your shower tray?


By all means get some building folks around but bear in mind the usual website sources are notorious for being stuffed full of cowboys, conmen and bodgers. And it sounds like you have met a typical candidate.