Damp wall drying out

Moonkat1992

Hi All,

We recently found some black mold growing above the skirting board on one of our external walls in the hallway - We've not lived here long and pretty sure the elderly ex owners had damp painted over in several places that was not picked up on our survey.

Anyway, we used mold killer on the wall and painted the area with fungicidal paint. We've also started turning the nearest radiator on again to try and warm the wall up as we've had it off for months which probably has contributed to the problem and have been using a dehumidifier after cooking.

The hallway is now much warmer and the wall felt warmer and drier. This morning I noticed a faint brown damp stain in the top corner of the wall (completely dry) beginning to show through the paint and some dry hollow bubbles at the top of the wall. Is this a sign that the wall is drying out and moisture is escaping or have we got a bigger problem?

Fire_Fox

Never harms to inspect your exterior wall in good daylight and/ or with an inspection lamp. Ideally consider each problem area in isolation as well as the overall picture.

Could be that the wall was not prepped correctly and/ or not dried out before painting over, or that different layers/ products were not compatible.

You mention cooking but not other major contributors to condensation: showering/ bathing, air drying laundry indoors and ... breathing! Are you using the dehumidifier daily to address these, and opening windows regularly (to let fresh air in too)?

Moonkat1992

I've had a look and it all looks okay, although a lot of the exterior pipework is just above that area of the wall. There was also a drain that was full of tennis balls and other rubbish which I cleaned out that was just under the wall. There's a crack at the top which seems to lead to a hollow area under the path to the base of the house so I imagine that wasn't helping either.

We have an extractor fan in our bathroom which we always use, but it doesn't seem very powerful. We bought a tumble drier as well as air drying laundry in our house just doesn't seem to work and putting things on the radiators turns the house into a rainforest. I open the bathroom window every morning and evening and the windows in the bedrooms most mornings, we're still condensated every morning but mainly upstairs. We seem to have two different lots of double glazing and we rarely get condensation on the other type downstairs.

I'm starting to think the very thick rock wool in the loft is the problem, the house was built in 1965 and just does not breathe

Fire_Fox

userdloat wrote: »

We have an extractor fan in our bathroom which we always use, but it doesn't seem very powerful. We bought a tumble drier as well as air drying laundry in our house just doesn't seem to work and putting things on the radiators turns the house into a rainforest. I open the bathroom window every morning and evening and the windows in the bedrooms most mornings, we're still condensated every morning but mainly upstairs. We seem to have two different lots of double glazing and we rarely get condensation on the other type downstairs.

I'm starting to think the very thick rock wool in the loft is the problem, the house was built in 1965 and just does not breathe

Many houses do not 'breathe' enough to cope with the large volume of water we release with current lifestyle choices, including air drying laundry indoors. Most people would consider a property that did 'breathe' very draughty and hard to heat!

You might try cleaning out the existing kitchen and bathroom extractor fans, replacing any filters or otherwise maintaining them (see user manuals), fitting more powerful extractor fans, replacing or rerouting their ductwork, opening windows and doors differently so the air circulates around the home, keeping bedroom doors ajar at night, taking shorter or less frequent showers, and/ or buying a decent dehumidifier.

Window treatments and window construction affect condensation.