Deck comparisons

Composite vs wood. Do the arithmetic on your own deck, not on averages. Take your square footage. Wood: installed cost at $15 to $25 per square foot, plus restaining every two to three years at $2 to $5 per square foot (or $4 to $7 once there's old finish to strip), plus replacement at 10 to 15 years. Composite: $28 to $40 installed, cleaning only, roughly 20 years. On a 300 square foot deck the up-front difference is a few thousand dollars and the staining bill over 20 years is real money. How long you plan to own the house is the deciding variable.

PVC vs composite. PVC/vinyl installs at $17 to $33 per square foot, composite at $28 to $40. Both eliminate staining. Judge them on the specific product's published performance and warranty documents, which you should read yourself rather than take from a salesperson.

Cedar vs pressure-treated. Cedar is $19 to $29 installed against $15 to $25 for pressure-treated. Cedar's decay resistance depends on heartwood content — 90 percent or more of the width on each side — so the grade matters as much as the species name.

Repair vs replace. For a 300 square foot deck, repair runs $500 to $3,000 and replacement $6,000 to $18,600. The standard advice is to replace when repair cost approaches new-deck cost, when the deck is more than 20 years old, or when beams and joists need replacing. Cosmetic problems favor repair. Structural ones do not.

DIY vs professional. Labor is $10 to $35 per square foot, so the savings are real. So is the risk: guard posts, ledger attachment, and footings are the three things that fail, and all three are code-governed and hard to inspect once built. If you DIY, still pull the permit and get the inspection.

How to choose

Pick your holding period first

Under about five years, wood's lower up-front cost usually wins. Over fifteen, composite's lack of a $2 to $5 per square foot restaining bill every two to three years usually does.

Compare like sizes

A 240 square foot deck runs $3,600 to $13,200. Every comparison you make should be on the same square footage and the same deck height.

Repair vs replace is a framing question

If joists, beams, or the ledger are involved, price the replacement. Sagging deck repair alone runs $750 to $10,000 — well into replacement territory.

Ground level vs elevated is the biggest structural cost line

Platform decks are $10 to $30 per square foot; raised are $25 to $50; two-story $30 to $60. Dropping the deck height is the cheapest design change available.

Covered decks are a different project

At $40 to $100 per square foot, a covered deck is closer to an addition. Expect different permit and structural review than an open deck.