Condensation on Pipes

[jkgreen]

I am having a problem with water soaking part of the wall around some pipes in my bathroom and would love some extra opinions! Plumber who came this morning said it was condensation and nothing can be done about it, but surely if left as is it will eventually lead to mould and ruin the wall?!

Full info:

I live in a maisonette flat, so it comprises first and second floor of the building (above a commercial property on the ground floor). The bathroom in question is on the first floor, and there are two water pipes running from floor to ceiling in one corner, set maybe an inch or two away from the wall itself. The room above the bathroom contains the boiler and hot and cold water tanks, so I've been told they are the pipes that bring in water from outside and take it up to the tanks.

When I moved in the bathroom needed redoing so was never used, but this year I got it refurbished including having a new shower put in. The problem now is that whenever the shower is used for anything more than a quick short shower, the walls around these pipes gets soaked! You can see the wet stain which extends from ceiling to halfway down the wall and must cover a few square feet in area (but only in the corner where the pipes are), and the wallpaper goes soft and soggy to the touch.

I've been told if it was a leak the area would be wet constantly but it's only when the shower is used. Plumber said the hot steamy conditions when the shower is running is causing condensation with the cold water pipe, which seems to make sense. But he says there is nothing to be done about it!? I feel like I just got a nice new bathroom and now nobody can use it! What am I supposed to do, keep using the shower until the wall rots and collapses?? Not to mention the big ugly stain on the wall is visible even after it dries.

The pipes are old painted metal pipes (copper I think?). Where they emerge in the upstairs boiler/water tank room the cold pipe is insulated, but it's not insulated in the bathroom - would insulating it fix the problem? Plumber said unlikely to help but I don't understand why not?

Any advice on this would be much appreciated!

 

[Chalked]

He is right. The steam from the shower will naturally condense onto a cold pipe.
To cure this the bathroom should be well ventilated. This can be as simple as opening a window, or installing an extractor fan as close to the shower area as possible and venting to outside. After that, if possible. Insulate the pipes and box them in.

 

[jkgreen]

He is right. The steam from the shower will naturally condense onto a cold pipe.
To cure this the bathroom should be well ventilated. This can be as simple as opening a window, or installing an extractor fan as close to the shower area as possible and venting to outside. After that, if possible. Insulate the pipes and box them in.

Hi, thanks for your response. I have no problem believing that condensation is responsible, I just couldn't understand why he didn't seem to think insulating the pipes would help!

The pipes are already boxed in, though it's far from an airtight box as old building = uneven walls so it's near impossible to neatly seal anything that involves straight edges! And there is an extractor fan, but again due to the building I couldn't install it directly above the shower as I had wanted to, so the pipes are closer to the shower than the fan is, but not much I can do about that.

Thanks again.

 

[Best]

There is always some humidity to the air, so you will get a lot of condensation on the mains pipe once it gets very cold when the underground water flows through it. Exactly the same as when you bring a can of drink out of your fridge and even on a warm day the can will get beads of water forming on it.
Make sure your fan actually does extract air properly and get the pipes fully insulated.
Only other things you can do is have air conditioning.

 

[rpm]

Don`t like the part about the wallpaper being soggy hope the walls were attended to during the refurb.

 

[jkgreen]

Don`t like the part about the wallpaper being soggy hope the walls were attended to during the refurb.

Walls were pretty much left alone during refurb as they were the only bit of the bathroom that was in good condition at the time! Smooth, dry and even been freshly painted before I moved in. Now I will have to paint again to cover the water stains, but there's no point until I fix the problem of course. Before the refurb there was only a rather disgusting ancient bath and shower so they were never used (as I have a second bathroom). It's only since the new shower was fitted, and the bathroom now gets used for showering, that the problem has cropped up.

Thanks for the advice all. I think I will definitely try insulation on the pipes as it's so cheap and easy to do it's worth a shot. Don't know why plumber said not to bother :/

 

[rpm]

Ah freshly painted sets my alarm bells ringing!

 

[rpm]

This started as a few drips into the garage below, The facing wall is brick with stud walls either side the Black is the damp spreading.

 

[jkgreen]

Ah freshly painted sets my alarm bells ringing!

It would mine, but then there were 4+ other parts of the house that had proper damp-eroded wall problems showing clearly and no attempt to hide/fix those! So I can't see them deciding to plaster and paint a corner in one bathroom and ignore the rest. Plus home report flagged up all other areas but nothing in that bathroom. Having seen how obvious the effect on the wallpaper is now, I'm sure previous water problems in that area would have been very evident. It does make me wonder if they actually used proper water-resistant bathroom paint or not, maybe that's exacerbating the problem with it soaking into the paper...

It's an old house that belonged to an old lady who passed away, little or no care had been taken of it in a few decades by the look of everything beyond layering more fresh paint on every now and then. Think avocado bathroom suites and orange shag carpets! lol Me and the house have a bit of a love-hate relationship sometimes but it's a work in progress

 

[john999uk]

I am not a plumber. The air in the bathroom after a shower will be very humid. When warm moist air hits a cold surface the water will condense out of it forming condensation. Fundamentally there are 2 ways to stop condensation forming. 1. Extract the moist air so it doesn't come in contact with the cold surface. 2. Insulate the cold surfaces so they are no longer cold.
I would say insulate the pipes and try and seal the boxing in to the wall, by good quality silicon sealant (good quality to stop mould forming on it).

You mentioned an extractor, I assume that it does keep running after you switch the light off? Maybe a decent humidistat controlled extractor would be better. As it would keep running till the moisture level was down to a reasonable level.