Deck Cost Calculator
What a new deck costs in pressure-treated wood, composite or hardwood, including labour.
Deck pricing is usually quoted per square foot, but almost nothing about a deck scales linearly. Railing is priced by the linear foot, stairs by the step, footings by the depth to frost line. A small deck costs more per square foot than a large one because the perimeter-to-area ratio is worse.
The material decision dominates the budget more than labour does. Pressure-treated pine installed runs roughly $35 to $45 per square foot; composite pushes $55 to $75; hardwood and aluminium can exceed $90. Composite costs more upfront and less over twenty years, which is the comparison worth making.
How this calculator works
Every field is editable and the result updates as you type — nothing is submitted anywhere, all the maths runs in your browser. That matters for a number you are about to spend money on: you can see exactly which input moved the answer, and by how much.
What this calculation assumes
Assumes a ground-level deck with normal access, a simple rectangular footprint and no demolition of an existing structure. Second-storey decks, complex shapes, engineered footings and permit drawings routinely add 30% or more.
Treat the result as an order-of-magnitude check rather than a final quantity. Product packaging changes, regional labour rates vary by a factor of two, and no calculator has seen your actual site.
Frequently asked questions
Wood or composite decking?
Pressure-treated wood is cheaper to install and easy to repair, but needs staining every two to three years. Composite costs 40 to 60% more upfront and needs almost no maintenance. Over twenty years the totals converge — composite wins on effort, wood wins on initial cash.
Do I need a permit to build a deck?
Almost always for anything attached to the house or above 30 inches. Permits require a drawing showing footing depth, ledger attachment and railing height. Skipping the permit can void insurance and force removal at resale, so it is rarely worth the saving.
How much can I save by building it myself?
Thirty to forty percent, which is the labour line. But deck failures are usually footing or ledger failures, and both are invisible once finished. If you are not confident setting posts below frost line and flashing a ledger correctly, hire that part out.
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