How much wood for a bookshelf?
A 36″ × 12″ × 48″ five-shelf bookcase in cherry: 4/4 sides and shelves with a 6/4 top.
Parts total 24.4 BF; with 15% waste you'd buy 28.1 BF — about $164.33 at our 2026-08 price estimates, weighing roughly 82 lb.
Cut list
| Part | Species | Qty | Thick | W × L | BF |
|---|---|---|---|---|---|
| Sides | Cherry | 2 | 4/4 | 11.25″ × 48″ | 7.50 |
| Shelves | Cherry | 4 | 4/4 | 11″ × 34.5″ | 10.54 |
| Top | Cherry | 1 | 6/4 | 12.5″ × 38″ | 4.95 |
| Back rails | Cherry | 2 | 4/4 | 3″ × 34.5″ | 1.44 |
Cost by species
| Species | Buy (BF) | $ / BF | Cost |
|---|---|---|---|
| Cherry | 28.1 | 5.85 | $164.33 |
Wide 4/4 cherry gets pricey — gluing shelves from two narrower boards can cut the per-BF price and looks fine once finished.
Why it's built this way
The load math that matters here is shelf sag: a 3/4″ cherry shelf on a 34-1/2″ span holds a row of hardcovers with only a whisper of deflection, but stretch the same shelf past 40″ and books will bow it visibly within months — sag grows with the cube of the span. If you widen this design, thicken the shelves to 6/4 or add a front edge stiffener. The 6/4 top isn't vanity either; a thicker top visually anchors the case and stiffens the sides against racking.
At the lumberyard
Cherry is where sapwood discipline pays: heartwood darkens to russet while sapwood stays blond forever, so a shelf with a sap streak will advertise it more every year. Buy an extra board's worth and cut show faces from all-heart stock, banishing sap edges to backs and bottoms. Gum pockets are cherry's other tell — small ones fill with finish, big ones belong on the back rails.