condensation and airbricks

[jefro666]

I have a terraced house set back from my left hand neighbour by 8 feet so obviously my living room hangs out the back of their house by the same amount. From the back corner to my patio doors is another 8 feet.
I am suffering from black markings on the walls although the they feel dry if I stick a penknife into the plaster. The floors are concrete. I checked the neighbour's garden and he hasn't anything leaning against my house.
Will an airbrick through the cavity wall fix what is probably condensation?
If so how high up?
Any and all advice very welcome.
Cheers

 

[^woody^]

It may or may not work, but its rare if this works in isolation if you have a condensation problem - you may need to deal with any condensation at source (kitchen, bathroom), heating use and even furniture layout

If the mould is near floor level there may be a blocked cavity causing a cold spot on the walls

Air bricks are normally fitted 1.8m up and 300mm in from a corner.

 

[jefro666]

I'll try the airbrick just in case but from what you've said the blocked cavity sounds about right. There's no immediately obvious source of any condensation.
Thanks for the advice.