High humidity plus lack of air circulation—the kind of conditions you can get in a cottage that’s mostly closed up over the off-season, say—is a recipe for mould. And mould can grow on practically anything, including the contents of your cottage library. No good—breathing in mould spores is dangerous. And reading a wet, musty-smelling book kind of ruins the experience.
To rehab your books, try these tricks (taking the proper mould-cleaning safety precautions if necessary, of course).
If the books are damp
When it’s dry and sunny out, take damp books outside and stand them on end to air the pages for about an hour. No sun? Sprinkle cornstarch between the pages of each book and seal them individually in plastic bags or a container for a few hours. Repeat if necessary.
Once the mould is dry
If the mould is visible, dust it off with a fine-bristled brush or a soft cloth. Or, try spraying sheets of paper towel with non-perfumed, all-purpose cleaner, waiting for them to dry, and then interweaving the doctored sheets between the pages of the book. This will help kill the mould.
Wait, what if it’s not mould at all?
If the book smells musty but the pages feel dry and brittle, it could be that high humidity has caused the cellulose in the paper to break down. Unfortunately, you can’t reverse this damage using mould-busting tricks. But you can at least keep the books away from moisture as much as possible. Don’t store them in the basement, attic, or shed, and, ideally keep them away from any room that generates a lot of humidity: the laundry room or bathroom, for example.