Deck material lists by size
Full takeoffs for the sizes people actually build. Each one is a real calculation you can adjust, not a rounded average.
| Size | Area | Deck boards | Material list |
|---|---|---|---|
| 8x10 | 80 sq ft | 12 | Full takeoff → |
| 10x10 | 100 sq ft | 15 | Full takeoff → |
| 10x12 | 120 sq ft | 18 | Full takeoff → |
| 12x12 | 144 sq ft | 22 | Full takeoff → |
| 12x16 | 192 sq ft | 29 | Full takeoff → |
| 12x20 | 240 sq ft | 36 | Full takeoff → |
| 14x20 | 280 sq ft | 42 | Full takeoff → |
| 16x16 | 256 sq ft | 38 | Full takeoff → |
| 16x20 | 320 sq ft | 47 | Full takeoff → |
| 20x20 | 400 sq ft | 58 | Full takeoff → |
| 12x24 | 288 sq ft | 43 | Full takeoff → |
| 16x24 | 384 sq ft | 57 | Full takeoff → |
Board counts assume 5/4x6 decking in 16 ft lengths with a 1/4" gap, straight layout, 10% waste.
Why these sizes
These are the dimensions that come up again and again: sizes that suit standard board and joist lengths, fit common lot setbacks, and do not waste half a delivery in offcuts. A 16 ft deck built from 16 ft boards has no butt seams at all.
If your deck is not on this list, the deck material calculator takes any dimensions and returns the same itemised list.
What each page includes
Decking, joists, rim and ledger, blocking, hangers, posts, footings and the concrete to fill them, fasteners, railing and stairs — each with the reasoning behind the quantity. The assumptions are stated on the page, and every one of them is something you can change in the calculator.