The complete 12 × 16 deck material list, counted for you: boards, joists, screws, posts and concrete, with the cost at example prices — and the full working, so you can check every number.
This page is the finished answer for the most-asked deck size: a 12 × 16 ft deck (192 sq ft), worked out with our deck material calculator at its standard settings — 5.5 in boards in 16 ft lengths running the long way, a ⅛ in gap, joists 16 in apart, straight pattern with 10% waste, and the example prices. Change any of it in the calculator and the list updates for your deck.
| Item | Qty | Each | Cost |
|---|---|---|---|
| Deck boards 5.5 in × 16 ft | 29 | $18.00 | $522.00 |
| Joists 2 × 8 × 12 ft | 13 | $14.00 | $182.00 |
| Rim boards 2 × 8 × 16 ft | 2 | $14.00 | $28.00 |
| Deck screws — boxes of 350 | 2 | $45.00 | $90.00 |
| Posts 4 × 4 | 12 | $16.00 | $192.00 |
| Concrete mix — 80 lb bags | 24 | $6.00 | $144.00 |
| Estimated total | $1,158.00 |
How the numbers are worked out: 26 board rows (144 in of width ÷ 5.625 in per board and gap), one 16 ft board per row, + 10% waste = 29 boards. Joists: 13 across the 12 ft width at 16 in spacing, plus 2 rim boards. Screws: 26 rows × 13 joists × 2 per crossing = 676 screws = 2 boxes. Posts: spaced no more than 6 ft apart both ways = 12 footings, at 2 bags of concrete each.
If your design runs 12 ft boards across the 16 ft width, the same deck takes 35 rows and 39 boards, 10 joists and the same 12 posts — $1,296.00 at the same example prices. The calculator shows both: set length 16 × width 12 for boards the long way (this page), or length 12 × width 16 for boards the short way.
Stairs are a separate list — the deck stair calculator works out risers, treads and stringers from your deck height. And if you are digging real post holes rather than using the rough 2-bags-per-footing allowance, the post hole concrete calculator gives the exact bag count for your hole size (about 4 bags per post for a 12 in × 36 in hole).
| Deck size | Boards | Joists | Posts | Concrete bags | Total |
|---|---|---|---|---|---|
| 10 × 10 ft | 25 | 9 | 9 | 18 | $946.00 |
| 12 × 12 ft | 29 | 10 | 9 | 18 | $1,032.00 |
| 16 × 12 ft | 29 | 13 | 12 | 24 | $1,158.00 |
| 16 × 16 ft | 39 | 13 | 16 | 32 | $1,495.00 |
Totals also include the 2 rim boards and the screw boxes, which are not separate columns. Railings, stairs, delivery and tax are not included in any figure on this page.
At this site's example prices, the full material list for a 12 × 16 ft deck (boards running the 16 ft length) totals $1,158.00: 29 deck boards $522.00, 13 joists $182.00, 2 rim boards $28.00, 2 boxes of screws $90.00, 12 posts $192.00 and 24 bags of concrete $144.00. That is materials only — labour, delivery, tax, railings and stairs are extra, and lumber prices vary a lot by store and season, so edit the prices in the calculator for your area.
29 boards at the standard settings (5.5 in boards, ⅛ in gap, 16 ft board lengths, straight pattern, 10% waste): the 12 ft width makes 26 board rows, and one 16 ft board covers each row. If your boards run the short way instead — 12 ft boards across the 16 ft width — the same deck needs 39 boards, because it takes 35 rows. Both answers are in the calculator: set length 16 × width 12 for boards the long way, or 12 × 16 for boards the short way.
The deck calculator allows 2 × 80 lb bags per footing and spaces posts no more than 6 ft apart, which gives 12 footings and 24 bags for a 12 × 16 deck. If you are digging real holes and want the exact bag count for your hole size and depth, use the post hole concrete calculator — a 12 in × 36 in hole for a 4 × 4 post takes about 4 bags per post, roughly double the rough allowance.
No — the $1,158 list is the deck platform itself: boards, frame, posts and concrete. Stairs are a separate list (our deck stair calculator works out risers, treads and stringers for your deck height), and railings depend on your design and local code. Most decks over 30 in above ground legally need a railing — check your local rules.
These figures are planning estimates only — not a guarantee and not professional advice. Mistakes are possible, including through an error in this calculator. Always check the quantities, sizes, spacings and depths with your supplier, a licensed builder, and your local building code before you buy materials or start work. The owner of this site accepts no responsibility or liability for any loss, cost, damage, injury, wasted material or failed inspection that results from using these estimates. Prices are examples to start from, not live prices or quotes.