DIY Doctor UK DIY Forums

Hi,

I bought a terraced property just over a year now. The property is about 30 years old.

When we moved in the master bedroom has some mould on walls and ceilings. We redecorated the room and invested in a dehumidifier and also got a surveyor to check the attic to find a reason for the damp and he said it was just condensation and that ceiling condensation was due to attic insulation not covering all attic floor space up to the external wall. We got an additional layer of insulation installed and advised the company who did to try to cover all attic floor space.

Since then the damp on walls are gone but there is a still a fine line of mould appearing along the exterior wall on the ceiling as well as on the windows

There is no ventilation system in the house and the windows do not have a vent. Do you think that a simple window vent would help solve this or are there any other avenues to explore? I think having the dehumidifier run all night every night would also help but I do not think this would be solving the root cause of the problem and cost a bit of money.

Thanks

Chris

Hi Chris,
You are right to try and get to the cause rather than simply treating the symptoms.

Has your exterior walls been treated with cavity wall insulation? Getting this done might be a possible cure. Increasing the ventilation will certainly help if this is possible.

You will be able to find a lot more information on condensation here, which should be useful: https://www.diydoctor.org.uk/projects/condensation.htm