Help me out - condensation

[anolderandwiserkitten]

In my kitchen. I have tried everything. 1950's detached bungalow, SW England.

I have condensation on the back wall. It used to be a pantry but we took it out and hoped it would dry up. Last summer I cleaned with mold killer and re painted the whole lot. I do not know what is causing this. I just know that mornings and when I cook the back wall (north end of kitchen with door in it) gets damp and then starts to stream with water. I keep cleaning the mold off but its a never ending task. The mold then spreads round the other walls.

I have established it is condensation. I have a dehumidifier running and it takes out 2 litres a day but still its damp..... and the mold grows. I am fighting a losing battle.

How can I cure it (short of not using the kitchen at all ....and even then it still gets condensation).

I think it's the combination of a north facing wall, removing the pantry and the new sealed windows. The wall is cold and any moisture (which used to escape through gaps in the old windows) goes straight to the wall. You need more ventilation as others have said and investigate the wall. Despite it having a cavity it could be more permeable as its aged, or guttering leaking.

2 litres is not actually so much - form a condensation website:

Our everyday activities add extra moisture to the air inside our homes. Even our breathing adds some moisture (remember breathing on cold windows and mirrors to fog them up?). One person asleep adds half a pint of water to the air overnight and at twice that rate when active during the day. To give you some idea as to how much extra water this could be in a day, here are a few illustrations:

2 people at home
can produce = 3 pints
Washing dishes = 2 pints
A bath or shower = 2 pints
Bottled gas heater (8 hours use) = 4 pints
Drying clothes indoors = 9 pints
Cooking and use of a kettle = 6 pints

Total moisture added in one day = 26 pints or 14.8 litres

I'm in the south west too, it's very damp. DH is from the SE and really notices the difference.
I run a dehumidifier about 7 months of the year. It makes a lot of difference but I still find traces of damp black mould in corners occasionally. I have to really keep on top of it.

and yes, heat the room AND run a dehumidifier.

But do get the extractor fans etc

Our old downstairs loo used to get damp and mould- it was the coldest room in the house so was acting as a dehumidifier for the house (and was next to the kitchen so got all the cooking steam etc too even though we did use the cooker hood).

We added a heater (small electric towel rail as it was uneconomical to add heating pipes) and a small Heat recovery ventilation unit. It extracted on a trickle setting permanently and could be boosted occasionally.

Made a massive difference and stopped all the mould.

I'll try and find a link for the one we got.

Here

How do they work Ear?

They constantly extract air, then replace it with fresh air from the outside. Unlike an open window or trickle vent it heats the air coming back in with the air going out through a heat exchanger. I think it claims about 75% heat recovery.

It did make the room feel much nicer, you could feel that the air coming out of it was a bit cooler than the ambient temperature but it wasn't cold iyswim. You can turn off the incoming air in the summer.