Even with the popularity of e-books, many of us still have collections of treasured physical books. But do we treat those books like the valued possessions we say they are? The following five tips will help you preserve the books you wish to keep.
Pay attention to heat, humidity, and light
In regard to storing books, the Art Institute of Chicago states: “Ideal levels are 68-72° F, with 40-50% relative humidity. Monitor temperature and humidity levels. Excessive fluctuations in temperature and relative humidity can be particularly damaging.” There’s no perfect agreement on the best humidity level, though. The British Library recommends 45-55 percent relative humidity and the Library of Congress recommends 35 percent. The State Archives of Florida provides this commonsense advice: “A good rule of thumb is, if you are hot and sticky, your books are, too.”
Why do temperature and humidity matter so much? As Cornerstone Book Publishers explains, “Hot and dry conditions will desiccate and embrittle leather and paper; damp conditions will encourage mold growth.” And the State Archives of Florida notes that changes in temperature and humidity cause paper and bindings to swell and contract at different rates, which causes warping.
All of this means you probably don’t want to store books in a garage or an attic, unless you have temperature and humidity controls in those spaces. You also want to keep them away from fireplaces, radiators, clothes dryers, and other sources of indoor heat. Bookshelves are best placed away from windows and outer walls because these are the indoor areas most prone to temperature and humidity fluctuations. And, keep books away from heat and air conditioning vents.
Excess light can also damage books. Sunlight and fluorescent light are the biggest culprits when it comes to fading, because of their high UV component. UV coatings for windows are one way to help protect your books.
Watch out for pests
Lots of pests are attracted to books. Keep your books away from any area that gets rats or mice, heeding the words of the Cornell University Library: “Both rats and mice use paper to make their nests, and many fine books have lost chunks of text through their jagged gnawing.”
Insects such as silverfish and carpet beetles are also attracted to books. Silverfish like warm, moist areas — one more reason to avoid such storage areas. Keeping book storage areas clean helps prevent insect problems.
Use good bookshelves
Which bookshelves are best? The Art Institute of Chicago provides this advice: “Book collections should be stored on bookshelves made from metal or sealed wood. Unsealed wood releases damaging acidic vapors into the environment and can accelerate the deterioration of books.”
Also, make sure the bookshelves are deep enough for your books, since books that overhang can warp.
Keep books upright, or in short stacks
In general, books are best stored upright — using bookends, if necessary, to avoid angling. Oversize books might need to be stacked, but keep the stack reasonably short because a tall stack can damage the spines of the books on the bottom. Cornerstone Book Publishers and the Yale University Library (PDF) both recommend a stack of no more than three books. Nora O’Neill, writing on The Bookshop Blog, suggests the stack be no more than 12 inches tall.
Pack books properly
If you have books you are keeping in storage boxes rather than on bookshelves, make sure you’re using boxes that won’t damage the books. Cardboard boxes should be acid-free and lignin-free (though pests can easily eat through cardboard, so keep this in mind). Certain plastics — polyester, polypropylene and polyethylene — are also safe for books. The Library of Congress recommends packing the books flat, with the largest ones on the bottom, or packing them with the spine down.
Once the books have been packed, consider this additional advice from Cornerstone Book Publishers about storing the boxes: “Always allow at least four inches of space between the boxes and the walls, ceilings, and floors (lift the boxes up on wooden pallets).”