What does a new deck cost by size and material?
Size and material do most of the work
Deck cost scales closely with square footage, but the material you choose can double or triple the price for the identical footprint. Pressure-treated pine is the least expensive decking material and remains popular for its low upfront cost, though it needs regular staining or sealing to last. Cedar and other naturally rot-resistant woods cost more but age attractively and need less chemical treatment. Composite and PVC decking cost the most up front, often by a wide margin, but need no staining or sealing over their lifetime, which changes the long-run comparison.
This calculator multiplies your deck's length and width by a cost per square foot or square metre that reflects your chosen material, so you can see the gap between materials on your actual deck size rather than a generic example.
Footings and substructure are not optional
Whatever decking surface you choose, the substructure below it, posts, footings, beams and joists, is what actually holds the deck up and must meet your local building code. Footing depth is usually tied to the frost line in colder climates, and decks attached to the house typically need a ledger board bolted and flashed correctly to avoid water damage to the house framing. These structural elements do not change dramatically with your choice of decking material, so do not assume a cheaper decking surface means a cheaper substructure.
Elevated decks, multiple levels, built-in benches, stairs and railings all add cost beyond the basic square footage, and railings in particular are priced per linear foot or metre rather than by deck area, so measure the perimeter separately if your design calls for a lot of railing.
Permits and inspections
Most jurisdictions in the US, Canada, the UK and Australia require a permit for a raised deck attached to a house, and inspectors typically check footing depth, ledger attachment and railing height before and after construction. Permit fees are a small fraction of the total project cost but skipping this step can cause problems when you sell the house, since an unpermitted structure can complicate a sale or an insurance claim.
If your contractor has given you a firm quote that already bundles permits, footings and decking into one number, use "Custom amount" in the calculator to check that total against the component estimate and see where the two differ.
Planning for the long term
Factor ongoing maintenance into your decision, not just the build cost: a wood deck's staining and sealing every one to three years adds up over a decade, while composite decking's higher purchase price is offset by minimal upkeep. Our renovation budget calculator can help you weigh the upfront cost against these maintenance costs over the years you plan to own the home.
Local frost depth, span tables and railing codes vary enough that a licensed contractor or your local building department should confirm the structural specification before footings are dug.
How it's calculated
Deck area × an installed cost per sq ft or m² for the chosen material, multiplied by a height factor (raised decks need taller posts, stairs and railings) and a regional factor. The split shows typical shares for materials, labor and extras.
Worked example
A 16 × 12 ft (192 sq ft) cedar deck at ground level: 192 × $40 = $7,680, of which about $3,450 is materials and $3,450 labor.
Frequently asked questions
+Is composite worth the extra cost?
Composite costs more upfront but needs no staining or sealing. Over 10–15 years the gap often narrows once maintenance is counted.
+Do I need a permit for a deck?
Usually yes for decks attached to the house or raised above a certain height (often 30 in / 76 cm). Check with your local building office.
+Why do raised decks cost more?
They need deeper footings, taller posts, bracing, stairs and code-compliant railings, all of which add material and labor.
+Can I build a deck myself?
A low, freestanding deck is a manageable DIY project. Attached or raised decks need correct ledger flashing and structural design.
+Can I use my own price per square foot?
Yes. Choose "Custom amount" under decking material and enter the rate from your quote.
