Deck Replacement: When to Replace and What It Costs

A wood deck that looks tired on top is often worse underneath — the boards you see are usually the last part to fail, not the first. Full deck replacement becomes the smart call when the framing, posts, or ledger connection have deteriorated past the point where patching makes financial sense, and knowing where that line sits can save you from pouring money into a structure that’s already condemned. Expect $30 to $60 per square foot installed for a complete tear-off and rebuild, meaning a typical 300-square-foot deck lands between $9,000 and $18,000.

Signs Your Deck Is Beyond Repair

Surface problems — graying boards, peeling stain, a few cupped planks — are cosmetic and fixable. Structural problems are what push you into replacement. Walk under the deck with a screwdriver and probe these areas:

• The ledger board — where the deck bolts to the house. Soft wood, rust streaks from fasteners, or missing flashing here is the most serious finding; ledger failure is the number one cause of deck collapses.
• Post bases — posts buried in soil or sitting directly on concrete wick moisture and rot from the bottom up. If the screwdriver sinks in a half inch, the post is done.
• Joists and beams — check the tops of joists under the deck boards, where water sits. Widespread soft spots, sagging spans, or joists spliced with scab lumber all point to replacement.
• Fasteners and hardware — corroded joist hangers and popped nails throughout suggest the whole structure was built before modern code and hardware.

Age is a useful tiebreaker. A pressure-treated deck built in the 1990s or early 2000s is at or past its 20-to-25-year structural lifespan even with maintenance, and it likely predates current code on footing size, ledger attachment, and railing strength.

Repair or Replace: The 50 Percent Rule

Contractors use a rough threshold: when repair costs approach half the price of a new deck, replace it. Swapping a dozen deck boards might run $500 to $1,000. Replacing a beam or sistering several joists gets you to $2,000 to $4,000. Once you’re also into post replacement and ledger work, you’re paying near-replacement labor to keep 25-year-old framing — and every repair after that is money spent on a dying structure.

There’s a middle path worth pricing: re-decking. If the frame genuinely passes inspection, a contractor can strip the boards and railing and install new decking over the existing joists for $15 to $25 per square foot. Two cautions from experience. First, have someone qualified actually inspect the frame after the boards come off, not before — hidden joist-top rot is routine. Second, if you’re switching to composite, check the joist spacing: most composites require 16-inch on-center spacing (12 inches for diagonal installs), and older wood decks framed at 24 inches will need added joists anyway, which erodes the savings fast.

What Full Deck Replacement Costs

Installed prices vary with material, height, and site access, but these ranges hold across most of the US:

• Pressure-treated pine: $30 to $40 per square foot
• Cedar: $35 to $50 per square foot
• Composite (Trex, TimberTech, Deckorators): $40 to $60 per square foot
• PVC decking: $48 to $65 per square foot

Demolition and disposal add $5 to $15 per square foot depending on how the old deck comes apart and local dump fees — figure $1,000 to $2,500 for an average deck. Second-story decks add 20 to 40 percent for the taller posts, beefier footings, and staging. Railings are a line item people forget: $50 to $150 per linear foot installed for composite or aluminum systems, which on a wraparound railing can rival the decking itself. Stairs run $150 to $300 per step. If you’re weighing board options, our decking material comparison breaks down lifespan and maintenance costs for each.

The Replacement Process, Step by Step

A straightforward ground-level replacement takes a crew three to seven days; elevated or complex decks run two weeks or more. Here’s the sequence:

1. Permit and design — nearly every jurisdiction requires a permit for deck replacement, and many require stamped plans for decks over 30 inches high. Budget $100 to $500 and one to four weeks of lead time.
2. Demolition — boards, railing, framing, and usually the old footings if they’re undersized.
3. Footings and posts — new concrete footings dug below frost line (42 inches or more in northern states), with post bases elevated on standoff hardware.
4. Ledger and framing — a properly flashed, through-bolted ledger, joists on hangers, and hurricane ties where required.
5. Decking, railing, stairs — surface installation, typically with hidden fasteners on composite.
6. Inspections — usually one at footings and one final. Don’t skip these; an unpermitted deck complicates insurance claims and home sales.

Code Upgrades You’ll Be Buying

Replacement means building to today’s code, not the code of 1998, and that’s a feature rather than a nuisance. Expect the new deck to include lag-bolted or through-bolted ledger attachment with proper flashing (not nails), larger-diameter footings, 36-inch minimum railing height with balusters spaced under 4 inches, graspable stair handrails, and lateral-load connectors tying the deck frame back to the house floor system. None of this is optional, and it’s a big part of why replacement costs what it does — you’re paying for a structure engineered to hold a crowd, not just a grill.

DIY or Hire It Out?

Tearing off and rebuilding a simple, ground-hugging 12×16 deck is within reach of a confident DIYer with a helper, and doing it yourself cuts the project cost roughly in half — materials for that deck run $3,500 to $6,000 in pressure-treated lumber. The parts that argue for a pro: ledger flashing details (the highest-consequence flashing job on your house), footing depth and inspection scheduling, and anything elevated. A hybrid approach works well — hire out demolition, footings, and framing, then install the decking and railing yourself over a couple of weekends.

Getting Quotes and Vetting Builders

Deck replacement quotes vary wildly — 40 percent spreads between bids on the same job are routine — so get at least three, and insist each one itemizes demolition, footings, framing, decking, railing, and stairs separately. A lump-sum number hides where the money goes and makes comparison impossible. Check that each builder carries a contractor’s license where your state requires one, general liability insurance, and workers’ comp; ask for certificates, not assurances. Deck-specific experience matters more than general remodeling credentials — ask to see two or three completed decks and, ideally, talk to an owner whose deck is five years old, because framing sins take a few winters to surface.

Contract details worth negotiating: a payment schedule tied to milestones (never more than a third down), a written workmanship warranty of at least two years on top of the material manufacturer warranties, and clarity on who pulls the permit — it should be the contractor, and a builder who suggests skipping the permit is telling you something about their footings too. Expect four-to-eight-week lead times in spring; signing in the off-season shortens the wait and often the price.

Ways to Keep the Budget in Check

Keep the same footprint so existing footing locations can sometimes be reused after inspection. Choose a rectangular design — every angle, curve, and level change adds labor. Get quotes in late fall or winter, when deck builders discount 10 to 15 percent to fill their schedule. And be honest about material math: pressure-treated saves $3,000+ upfront on a mid-size deck, but if you’ll pay someone $400 to $800 to clean and re-stain it every two to three years, composite closes the gap within a decade. Whatever you build, plan to protect it from day one — a new wood deck needs its first coat of finish within a few months, and our deck painting guide covers that process when the time comes.