Everyday
Deck Cost Calculator
Price a deck from its size and material, get a full shopping list of boards, joists, and fasteners, and see the annualized cost of keeping it.
How it works
Behind the numbers
Enter the deck's length and width, the board width and gap, and the joist spacing. The calculator figures how many board rows fit across the width, converts that to linear feet of decking with your waste allowance, then counts joists from the spacing and prices the job at your per-square-foot rate.
Fasteners follow the material: wood decks get screws, two per board at every joist crossing; composite and PVC get hidden clips, one per crossing. Footings are estimated from post spacing, with a pointer to the concrete calculator for the actual bag count. Railing, stairs, and the permit fee are added as line items.
The maintenance box annualizes the real comparison: installed cost spread over the material's expected lifespan, plus a yearly upkeep rate you can edit. Pressure-treated needs staining every few years; composite mostly needs washing. All prices are editable estimates.
FAQ
Questions, answered
How much does it cost to build a deck?
Installed prices commonly run $15 to $70 per square foot depending on material, from pressure-treated at the low end to PVC at the high end. A 12 by 16 foot deck at the default pressure-treated pricing comes to about $4,474 including a $250 permit; adjust the per-square-foot price to match quotes in your area.
How many deck boards do I need?
Divide the deck width by the board width plus the gap, round up to full rows, and multiply by the deck length. A 12-foot-wide deck with 5.5-inch boards and quarter-inch gaps needs 26 rows, or about 458 linear feet of decking for a 16-foot deck with 10% waste. The calculator does this from your dimensions.
What joist spacing should a deck use?
Sixteen inches on center is standard for boards run straight. Composite or PVC boards run diagonally need 12-inch spacing, which adds roughly a third more joists. The calculator warns you when the material and spacing combination looks off.
Composite vs wood decking: which costs less over time?
Wood costs less up front and more in upkeep: plan on staining every two to three years, and expect 10 to 15 years of life from pressure-treated. Composite costs roughly twice as much installed, needs little beyond washing, and lasts 25 to 30 years. The annualized cost box puts both on the same per-year basis.
Do I need a permit to build a deck?
Often yes, and the rules are local. The calculator includes a permit line item with a $250 default; check with your city or county before building, since some areas also require inspections at the footing and framing stages.