We have this weird, grey mould on the ceiling in the bedroom and on two exterior walls - see pic attached.
It doesn't appear to be the type of black mould that you find in bathrooms. Can anyone tell us more about it, what causes it and what we can do about it, please?
We are worried that our landlord will blame us for it, but we're very conscientious tenants, we keep the flat as well ventilated as possible (not all the windows open), we dry all our clothes in the dryer and keep the heating on, even during the summer.
Thanks in advance.