Diagnose source of damp

[rockcrock]

Hi,

Moved to a new place a couple of months ago. We knew we had mould in the kitchen, have now removed a couple of units (we're doing the kitchen anyway) and can see more. The wall is an external wall.

Kitchen is not well ventilated, hob fan is not an extractor, no trickle vents on windows.

We have had conflicting diagnoses. One guy said it's the cavity wall insulation gone damp, but he didn't drill into the wall to prove that.

Another person said it's mould due to condensation, which makes the most sense as there's bad ventilation and external walls. But we want to make sure before we put the new kitchen in.

Any advice would be good thanks.

 

[blup]

It could be damp from the wall but more likely the other factors you mention. Kitchens produce a lot of moisture and it will settle in the colder corners against an external (colder) wall. The physical presence of a washing machine etc which is constantly heating and cooling etc would probably contribute to the mould. Wipe the wall down with a mould remover/inhibitor and let it dry out, then plan the best ventilation you can for the new kitchen.

Blup

 

[^woody^]

That's classic condensation, not structural damp.

Treat the mould with a fungicidal wash, and fit a suitable extract fan.

 

[berty3000]

Lack of ventilation over many years behind units against an outside wall, which moisture condenses against. Very common in kitchens, not a big deal. Clean off with watery bleach solution and treat the wall with an anti fungal paint. Good ventilation practices in future will help, but probably inevitable in the long term behind kitchen units.

 

[rockcrock]

Thank you all for the responses, appreciate you taking the time. Definitely plan to add extraction!