What should I check on airbricks in an old house that get damp around them?

[Gary111]

I get moldy patches round my airbricks that vent into the rooms.

I have just read in an old diy book that they should have telescopic liners between the internal and external vents and also have cavity trays above them.

Does this apply to an old house around 1900) as it sounds like it may be the cause of my damp issues?

Thanks

 

[jeds]

You almost certainly have terracotta vents. The mould is due to cold bridging through the vent walls. Tricky to eliminate entirely but may indicate that you room has a higher level of water vapour than normal.