If you have bookcases on each side of your fireplace and the shelves are deeper than the normal 10 to 12 inches, don’t push the books all the way back against the wall. In fact, you should do exactly the opposite.
Line up all of the books with the front edge of the shelves. Leave the varying depths in the space behind the books. Rooms look much better that way.
After filling up most of the shelves with books, if you still have open space, put a few smaller books horizontally in those spaces. Those open spaces will also allow you to have a place to put down a couple of books as you’re browsing or adding more to the collection.
You can use two or three thick books as bookends, leaning them against the end of a row of books. In addition, heavy pottery or heavy glass vases work well in place of traditional bookends.
If you have some framed photographs you’d like to display, place them forward, parallel to the edge of the shelf, with the surrounding books tucked right up next to them.
If you’re building a new bookcase that has several sections, line up the shelves in each section left to right. You could start out with all of the upper shelves 8 inches tall, then 10 inches for the next row, a couple of 12s after that and then one that has a 14-inch space.
At 30 to 36 inches from the floor, create a 5- to 6-inch-tall shelf. It makes a very good looking layout and provides space for large books in a horizontal stack.
It also creates a nice texture if filled with CDs. It is like an accent ribbon at the height of most doorknobs.
The two bottom shelves below that should be about 14 inches and 18 inches to make room for the very tall books that we all have.