DIY Doctor UK DIY Forums

Hi all,

new to the forum today and hhave a damp problem. We have a new baby (2 weeks oldd) and condensation damp in the outside wall corner. We have just had a complete new roof and guttering redone to a high standard. We don't have an air brick in the chimney breast in the bedroom, will it help if I put one in?

It is an old farm house with double brick walls and no cavity. I am worried that we may get the black mould reappearing with the little 'un in the room. We need a solution pretty quick, any ideas?

fit trickle vents to the windows.

Sorry Welsh Brickie but I have to step in here..

Trickle vents on windows such as UPVC do not give the required amount of ventilation and airflow to combat high relative humidity levels that cause condensation and subsequent mould growth. I would always recommend installing high level passive air vents to each room which give better air flow and reduce humidity levels.
Some builders make the mistake of putting the vents at low level which is where you find most of the condensation and mould but warm humid air rises so it's at high level where they are most effective.
1 air brick on its own will not be sufficient as you need to get air circulation and 1 air brick on its own cannot push and pull air at the same time.

The vents should be placed as far away from eachother as possible obviously on external walls at approximately 12" from the ceiling.

If you wanted to go one step further, addressing the source of humidity will dramatically improve the situation. Rooms such as kitchens and bathrooms cause the most water vapour and as such are the primary rooms to start ventilation. Make sure your bathroom has a decent extractor fan which is turned on when having a bath or shower and your kitchen also has some form of extraction for when cooking.
If these areas are well ventilated, you reduce the need for additional ventilation in other areas.