In Peter Walsh’s It’s All Too Much Workbook (the companion piece to his popular It’s All Too Much) he discusses the physical limitations of storage and how to use math to determine how much you can keep and have your home be clutter free.
From page 63:
While you are figuring out what fits where, there is a concrete way to measure your space for what it can contain. I’ve said it before: You can’t fit four cubic feet of stuff into two cubic feet of space and not have clutter. So get out your tape measure and see what will work in the space you have.
First, measure your shelving space or bookshelves or hanging space and use the table below to work out how many of a particular item will fit.
Peter provides the following “cheat sheet” to identify how many of one item will fit into a linear foot of space:
VHS tapes — 11
DVD cases — 20
CDs in jewel cases — 29
Magazine box with 10 magazines — 3 (30 magazines total)
Books — 12 (on average)
Jeans/pants — 12
Shirts/blouses — 15
Heavy jackets/suits — 6
Shoes — Estimate about 8 inches per pair
To put his numbers to work, let’s look at his estimation that books average about an inch a piece. To properly store 100 books, you should have 100 inches of bookshelf space. The popular Expedit bookcase from Ikea has shelves that are 13 inches, so you would need 7 shelves of an Expedit bookcase to hold 100 books. Since there are 16 shelves on an Expedit bookcase, you could store approximately 208 books total on the shelves.
Knowing exactly how much storage space you have and exactly how many items you can store in that space can make it easier to decide what to keep and what to purge. Let the math do the work.