One of the questions I sometimes get as a Librarian is, why is it cold in the library, even in the winter?
The answer is: climate control. Especially in older libraries, you will see windows that could be opened but aren’t, even on lovely days. The reason has to do with the preservation of the materials within the building.
Ideally, books should be kept at 68-72F and 40-50% humidity. Actually, ideally, the temperature should be in the 50sF, but then it would be just a bit too nippy for humans and the cost of keeping a building that cold would be….significant.
What does this mean for you as an owner of books?
If you want your books to survive longer, there are several things you can do in order to promote longevity among your collection. First, realize that a book isn’t forever. Sure, we have papyrus manuscripts from the Ancient Egyptians and the Gutenberg Bibles were printed in the 1450s and they are still around, but the material that has been used for printing has changed pretty drastically over the last couple of hundred years. Before the late Victorian period, books were printed literally on cloth. Rags were collected, then macerated in a foul smelling mash until the fibers started to come apart. Then it went through several more processes until it got to the goop stage (not an actual technical term) where it was spread out on screens, allowed to dry a bit, and then peeled off the screen to completely dry and voila! Paper. Actually, this video will show you more – it’s a bit vintage and this paper mill has since closed. Making paper was expensive and there was a dearth of rags going around. Eventually, a process was figured out on how to make paper from trees and modern paper making was born.
Why the history lesson? Because paper made from trees is highly acidic whereas paper made from cloth, not so much. Today’s paper is actually more alkaline and will last longer than paper made in the 1990s, which was actually more acidic. In the library world, this whole issue was known as Brittle Book Syndrome and there was a great fear that after having spent all of the time and money to acquire collections of books, that they would literally turn into dust due to acidification. (Here is probably more than you ever wanted to know.)
The books in your home are probably a combination of acidic and alkaline paper depending on when they were printed. No, you don’t have to separate them out. Being aware however of the process involved in the degradation of your books does help you preserve them better. If your books are turning yellow, especially after a decade or two, then the paper is definitely acidic. If you want to know how acidic they are, the library world will often use the double-fold test to determine how bad off paper is. I don’t actually recommend doing the test, in part because the test is going to permanently damage at least one page in the book. Suffice it to say, if you turn a page and it starts tearing, you are probably looking at some seriously acidic paper. Any book in that state should definitely be isolated from others and honestly, it should be encased. There are other worst case scenarios, but let’s pretend that you are an average book owner and you’ve got a wide range of books from hot off the press to perhaps a couple of childhood favorites.
Where NOT to store books
Do NOT store your books in the basement or the attic. Remember that question about why is it so cold in the library? It’s dry there too. The attic is too hot in the summer and too cold in the winter. The basement is typically a good temperature, but far too damp and dampness would promote mold growth, something you definitely do not want. Also, avoid putting books in the kitchen area or bathrooms. Yes, I am a bathroom reader. Yes, I have books in my bathroom. No, they do not live permanently there. A little humid air for a short time won’t permanently damage a book, but repeated extended exposure will.
Having your books in bookcases is good and having those books away from direct sunlight is even better. Being in the sun will promote fading on the spines and will also heat the books up. It’s not a big deal if you are sitting in a sunbeam and having a nice afternoon read. However, if a book is subjected to a daily sunbath for twenty years, it’s going to show that much light exposure.
Keep ’em clean!
Dust that collection! Do it on a regular schedule. When you move, as I did recently, really spend time thoroughly dusting every edge of the book. You’ll be surprised at how much dust there is. I used to dust my collection once a quarter, but now that I live in a dustier environment, I try for once a month. Books should also be standing up on their bottom edge and not stacked on top of each other. This is more of a space thing, however having your books snug in a bookcase is better for them. If you’ve got quite a bit of space on shelves, use bookends to snug up the row of books. When you don’t use a bookend, the couple of books on the end usually warp because they are placed at an angle. Warping often occurs more in the spine than in the paper, but I’ve seen it happen to both spine and paper. Bookends can be simple and utilitarian or not.
Keep an eye on it
Finally, keep an eye on your collection. If you start seeing silverfish or other other book loving insects, they typically aren’t after the paper in the books, but rather, the glue. Glue was traditionally made from animals. There are a wide variety of glues these days but there are still varieties that are made from starches that insects will like. If you do have silverfish or other insects, they probably weren’t attracted by the books, but once they found them, the books were an enticement to stay. Often, the bugs were initially attracted to dampness, especially silverfish, so you might have a leaky pipe somewhere. (Can you tell I’ve had to fight a silverfish infestation?)
Your books will last a good long time, decades and even centuries, if you treat them well. Be good to your books and they will be good to you!