You are reading a single comment by @BRM and its replies.
Click here to read the full conversation.
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
BRM
Thanks for the comprehensive reply, I don't think airflow is a reason as the window is always left open slightly and even when shut lets in a draft.
So builders have who did work on the property a few years ago have inspected the mushroom...
It turns out when the security bars were fitted to the exterior of the building, the guy who did it didn't consider that the basement of the house (where that window is) was tanked. Therefore he put a stud straight through the damp course, which is probably the cause of the problem.
Luckily its not my house and will be signing contracts on my new place by the end of the month.