damp patches, what is the cause?

[Late74]

Hi im after some advice if possible, i had cavity wall insulation fitted in Nov 2009, about 12 months later we started to get mould patches in the kitchen and the upstairs bedrooms. I wiped with bleach many times but it comes back, i have recently again just redecorated the upstairs bedrooms and 2 months on nothing has of yet returned.

I had never gave it anythought to the reason why we were getting mould patches, and we keep our home warm so didn't know why. but just a couple of weeks ago i was discussing it with a work colleague who asked if i had cavity wall insulation fitted and he then suggested that might be the cause! i have since had a look online and have also stumbled across someone saying that in certain types of construction it should never be fitted and can cause structural damage, one of which is ours which is concrete construction.

but there are many conflicting articles on the subject and wanted some other peoples advice / opinion.

i have also read about people removing bricks to have it removed but i have no bricks just concrete constructed walls that are rendered.

anyway any help would be great

 

[JohnD]

please tell us how you ventilate your home.

Photos of the patches would help.

 

[TicTac]

Is the house warmer now, and what are the weather conditions like. Wales is reckoned to be a no no area for CWI as it rains so much there, the water seeps across the insulation. Who installed the CWI.

 

[^woody^]

Whether the insulation is installed fully or not (creating cold spots for condensation), the issue issue is invariably related to lack of or poor ventilation.

Insualtion just amplifies an existing ventilation problem