Damp in boiler cupboard

Britannia12345

We've lived here just over a year and never had damp until this turned up in the boiler cupboard. The kitchen wall is on ine side and the chimney breast on the other.

We had the chimney removed before christmas - could that be causing the damp?

Grumpy_chap

What exactly was done when the chimney (but not the chimney breast) was removed?

Was the chimney previously open?

If so, what alternative ventilation is in place?

casper_gutman

I think I'm thinking along the same lines as Grumpy_chap. It's possible for removal of a chimney that was previously open to cause damp issues if ventilation of the redundant flue isn't addressed, as hygroscopic substances deposited inside as a result of historic burning of coal will absorb moisture from the air.

Britannia12345

There's just the open chimney into the front room with an electric fire in front of the space.

jonnydeppiwish!

Is that a cold water pipe? Might be worth lagging it to prevent condensation?

Spikeygran

What I'd do in this sort of situation is get the mold treated, then wash the walls and floor (wear a good mask etc ) so you can see whats going on and put a dehumidifier in there for a few days or until its nice and dry. If you have cheap electric you can set it to come on at those times.

Then check up on it over the next week or so and see where the moisture is entering. A damp meter might help identify which wall is highest in moisture?

The worst of it looks to be wherever the cold pipe is. The water coming in is significantly colder especially with the boiler in there, so condensation off that pipe looks likely. But for there to be condensation there has to be some element of damp in the cupboard - its the boiler warming slightly damp air that then condenses on the pipes and drips off.

Theres a patch in the corner in the first photo which looks wet as opposed to damp. If its under the boiler check for leaks first. Is that corner on an outside wall, if so whats on the outside. Is there any earth over the dpc, patio tiles with a build up of earth between wall and tile, that sort of thing.

The point where the water pipe comes through looks worse too, so check for leaks there. Once youve ruled out actual leaks, getting the cold water pipes really well lagged and maybe spray foam where the pipe comes through the wall. Check from the outside and insulate there it all helps.

If you ruled everything else out then you might have to get hold of whoever did the chimney for advice. If theres any section of the chimney void left they can take a long time to dry out. Sometimes airbricks are fitted but theres different views on those.

Spikeygran

I've just had a thought (it happens occasionally lol)/

I assume thats a condensing boiler? In which case it should have a condensate pipe (that drips water residue from the process). Ours is a flexible pipe that goes to an open drain in the garage. If thats got blocked or pipe has come off or perished you would have a regular drip.

bjorn_toby_wilde

Are you absolutely sure this is recent? Looking at those plaster marks it looks like it’s been going on for quite a while to me.