Deck calculator
Boards, framing, footings, hardware, railing and stairs for a rectangular deck.
Job
Deck
Decking
Boards
Fasteners
Framing & footings
Railing & stairs
Calculated — type to override
Materials list
| Item | Qty | Unit price | Cost |
|---|---|---|---|
| Decking | |||
| Deck boards (5/4×6)26 rows × 16 ft | 28 pcs (16 ft) | $ | — |
| Deck screws, 2-1/2 in.two per joist crossing | 3 boxes (≈350) | $ | — |
| Framing | |||
| Joists (2x8)16 in. on center, 12 ft span | 13 pcs (12 ft) | $ | — |
| Ledger & rim boards (2x8) | 2 pcs (16 ft) | $ | — |
| Beam plies (2x10)1 beam(s), 2-ply | 2 pcs (16 ft) | $ | — |
| Blocking (2x8)1 row(s) | 2 pcs (16 ft) | $ | — |
| Posts (6×6)4 posts × 3 ft | 2 pcs (8 ft) | $ | — |
| Footings | |||
| Concrete mix (80 lb)4 holes, 12 in. × 36 in. | 18 bags | $ | — |
| Post bases (6×6) | 4 ea | $ | — |
| Post-to-beam caps | 4 ea | $ | — |
| Hardware | |||
| Joist hangers (2x8) | 13 ea | $ | — |
| Hurricane ties | 13 ea | $ | — |
| Joist hanger nails, 10d × 1-1/2 in. | 2 lb | $ | — |
| Ledger fasteners (1/2 in. lags or structural screws)two every 16 in., staggered | 24 ea | $ | — |
| Ledger flashing | 2 pcs (10 ft) | $ | — |
| Joist tape (butyl) | 5 rolls (50 ft) | $ | — |
| Railing | |||
| Rail posts (4×4, 2 per 8 ft)8 posts | 4 pcs (8 ft) | $ | — |
| Rails (2×4, top & bottom) | 6 pcs (16 ft) | $ | — |
| Rail cap (2×6) | 3 pcs (16 ft) | $ | — |
| Balusters (2×2 × 36 in.)3.5 in. gaps (4 in. max) | 96 ea | $ | — |
| Carriage bolts 1/2 × 8 in. (with nuts & washers) | 16 ea | $ | — |
| Baluster screws, 2-1/2 in. | 2 boxes (≈350) | $ | — |
How it works
- Joist sizes are rough maximum spans for southern pine #2 at your spacing (AWC DCA 6). Other species span less — check the tables and your local code.
- Board rows = deck depth ÷ (board width + gap). Boards are laid out on your board length so offcuts are reused.
- Add your supplier's unit prices to any line for a cost estimate; tax and markup are optional.
How to measure
- Length runs along the house (or the long side), depth runs out to the beam. Height is from grade to the top of the decking.
Estimates only. Coverage, sizes and waste vary by product and job — verify with the manufacturer's specs and your local building code before ordering.
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