One of our tenants recently reported a damp/Mold issue with one of our properties.
After inspection, the extractor fan in the bathroom was found to be faulty, and was likely letting condensation settle on colder walls , causing Mold.
The tenant was provided with a moisture meter to track the humidity within the property, and a new extractor fan was installed.
After a couple of months, the tenant reported, the moisture in the air of the property had improved significantly , and the Mold problem has been resolved.
Always inspect your extractor fans, and replace with the latest models as soon as possible. These devices make a huge improvement in Mold/moisture problems in most homes.