Original sentence: Most commonly they are encountered in basements, bathrooms, and lavatories, which tend to be humid, but they can also be found in drier places like offices, bedrooms and dining rooms
Edited sentence: Most commonly they are encountered in basements, bathrooms, and lavatories, which tend to be humid, but they can also be found in drier places like offices, bedrooms and dining rooms, where they are attracted by dirt and mess left behind by bad housekeepers