Deck FAQ

Most deck questions reduce to two: what does it cost, and what will the inspector want. Cost is answerable from national ranges as a sanity check — $9,000 to $20,000 for most builds — but only local bids give you a real number, because labor alone spans $10 to $35 per square foot.

Code questions are different. Some answers are prescriptive across the widely adopted model code: guards above 30 inches of grade, 36-inch minimum guard height, 4-inch sphere limit, 7 3/4 inch maximum riser, 10-inch minimum tread, handrails on stairs with four or more risers at 34 to 38 inches. Others — frost depth, setbacks, permit thresholds — are purely local.

The recurring theme in what goes wrong is water and connections. Rot repair costs $300 to $5,000, and it starts at the ledger, at post bases, and under things left sitting on the boards. Almost every expensive deck problem traces back to one of those three.

If you only remember one thing: get the permit, attend the framing inspection, and don't use the deck until it has final approval.

How to choose

Cost questions: get three bids

National ranges are for sanity-checking. A $15 to $55 per square foot spread is too wide to plan against.

Code questions: split national from local

Guard and stair geometry are prescriptive. Frost depth, setbacks and fees are not.

Material questions: answer with your maintenance habits

Wood needs restaining every two to three years at $2 to $5 per square foot. Be honest about whether you'll do it.

Repair questions: assess the frame first

Repair at $500 to $3,000 versus replacement at $6,000 to $18,600 for 300 square feet turns on the joists and the ledger.

Value questions: assume about two-thirds back

65.8% wood, 63% composite. Plan the budget around use, not resale.