Deck Replacement Cost Calculator

In 2026, deck replacement typically costs $20 to $55 per square foot, so replacing a 300-square-foot deck runs roughly $6,000 to $16,500, with the price depending heavily on how much of the deck you replace. The single biggest factor is the replacement scope: simply re-decking the surface (replacing the boards and railing while reusing a still-sound existing frame and footings) is the most affordable, replacing the boards plus the framing is mid-range, and a full tear-out and rebuild (including new footings) is the most expensive. The new decking material also matters — pressure-treated wood is the cheapest, cedar/natural wood is mid-range, and composite (like Trex) and PVC cost more upfront but last longer with less maintenance. Height is another factor: a ground-level deck is cheaper to replace than a raised or second-story deck that needs more substructure work. The cost also includes tearing out and disposing of the old deck, and add-ons like upgraded railing, deck lighting, joist flashing tape, rebuilding stairs, and permits add to the total. Because replacement involves demolition of the old deck plus building the new one, it differs from a fresh new-deck build (no existing structure) and from a simple repair (fixing isolated damage). This calculator lets you set the size, scope, material, and height to estimate your deck replacement. Pricing varies by region, deck complexity, and contractor.

The choice between re-decking just the surface and fully replacing the deck hinges on the condition of the substructure (the frame and footings underneath), and it's the most important decision for both cost and safety. Re-decking (also called resurfacing) means replacing only the deck boards and usually the railing, while reusing the existing joists, beams, posts, and footings — it's significantly cheaper and faster because the structural work and footings are already done, and it's a great option when the frame is still solid: no rot, no significant cracking, properly sized and spaced joists, secure connections (especially the ledger board where the deck attaches to the house), and code-compliant footings. However, re-decking only makes sense if a thorough inspection confirms the substructure is sound — covering up a deteriorating frame with nice new boards is dangerous, because deck collapses almost always stem from structural or connection failures, not the boards. Full replacement (tearing out everything, including possibly the footings, and rebuilding) is necessary when the frame has rot, insect damage, undersized or improperly spaced joists, failing or non-code connections (a common issue with older decks is an improperly attached ledger), bad or heaved footings, or when you want to change the deck's size, shape, height, or layout. It costs more but gives you a fully new, code-compliant, safe structure. A middle option is replacing the decking and some or all of the framing while keeping good footings. The safe approach is to have a contractor (or inspector) evaluate the substructure first: if it's solid, re-deck and save money; if it's compromised, replace it. Older decks (especially those over ~15-20 years or built before current codes) more often need full replacement. This calculator lets you choose the scope — surface, frame-and-surface, or full rebuild — to match your deck's condition.

Several warning signs indicate a deck needs replacing (or at least major structural work), and because deck failures can cause serious injury, it's worth inspecting carefully or having a pro assess it. Key signs include: rot and decay — soft, spongy, or crumbling wood (probe suspect areas with a screwdriver; if it sinks in easily, the wood is rotted), especially in the joists, beams, posts, ledger board, and stair stringers; loose, wobbly, or swaying feel — a deck that moves, sways, or feels unstable when you walk on it suggests failing connections or structure; corroded, missing, or loose fasteners and connectors — rusted nails/screws, missing joist hangers, or a ledger board attached with just nails (rather than proper bolts/lag screws and flashing) are serious red flags, since improper ledger attachment is a leading cause of deck collapses; cracking and splintering boards — widespread cracking, splintering, warping, or cupping of the decking; wobbly or loose railings — railings that move or aren't secure are a fall hazard; rot or movement at the posts and footings — posts in contact with soil, heaved or cracked footings, or posts not properly anchored; and insect damage (termites, carpenter ants) in the wood. Age also matters — wood decks generally last about 15-25 years (less without maintenance), and a deck built before modern codes may not meet current safety standards even if it looks okay. If the damage is isolated (a few boards), a repair may suffice; if it's widespread, structural, or connection-related, replacement is the safer choice. Given the safety stakes, have any deck showing structural signs, instability, or significant rot evaluated by a professional. This calculator estimates replacement; for isolated damage, see the deck repair calculator.

These three deck projects overlap but differ in scope, cost, and when each applies. Building a new deck (new construction) means adding a deck where there wasn't one before — it includes the full process of design, permitting, footings, framing, decking, and railing on a clean site, with no demolition of an existing structure; this is for homeowners who don't currently have a deck. Deck repair means fixing specific, isolated problems on an existing deck that's mostly sound — replacing a few rotted or cracked boards, tightening or re-securing railings, replacing some fasteners or a joist hanger, fixing a stair tread, or reinforcing a connection; it's the most economical option and makes sense when the damage is localized and the overall structure is safe. Deck replacement means removing an existing deck (in whole or part) and building a new one in its place — it's chosen when a deck is too deteriorated, unsafe, or outdated to repair, and it can range from re-decking just the surface (reusing a sound frame) to a full tear-out and rebuild; it includes the demolition and disposal of the old deck plus the new construction, which is why it differs from a from-scratch new build. The decision ladder is roughly: if the deck is fundamentally sound with isolated issues, repair; if the boards are worn but the frame is solid, re-deck the surface; if the structure (frame, footings, connections) is compromised or you want a different deck, replace/rebuild; and if there's no deck yet, it's new construction. Cost rises along that ladder. This site has separate calculators for new deck construction, deck repair, and this deck replacement calculator, plus composite/Trex decking, so you can estimate whichever matches your situation.

You can often reuse the existing frame and footings when replacing the deck boards, but only if they're structurally sound and code-compliant — and that requires a careful inspection before you decide. Reusing the substructure is the basis of the economical 're-deck the surface' approach: if the joists, beams, posts, footings, and the critical ledger connection are in good shape, you can strip off the old decking and railing and install new boards (and railing) on the existing frame, saving a lot of money and time. What to verify before reusing the frame: the joists and beams should be free of rot, significant cracks, and insect damage (probe them, especially the tops where water sits and the ends near connections); they should be properly sized and spaced for the new decking (note that some composite boards require closer joist spacing — often 12-16 inches — than older decks may have, which can require adding joists or 'sistering'); the ledger board (where the deck attaches to the house) must be properly bolted/lagged and flashed (a frequent deficiency in older decks and a top cause of collapses) — if it's just nailed or lacks flashing, it needs correction; the posts and footings must be solid, properly anchored (post bases, not buried in soil), and not heaved or cracked; and all connections and hardware should be sound (proper joist hangers and connectors, not rusted). Even when reusing the frame, contractors often add protective joist flashing tape over the existing joists before installing new boards to extend the frame's life (an add-on here), and may upgrade some connections to meet current code. If the inspection reveals problems, you may reuse some elements (like good footings) while replacing others (the framing) — a partial replacement. If the frame is widely compromised or undersized, a full rebuild is safer. This calculator lets you pick the scope based on what your substructure inspection finds. A contractor's evaluation of the frame is the key first step.

Replacing your deck is a good opportunity to choose a decking material that fits your budget, maintenance tolerance, and how long you plan to keep the home, and the main options are pressure-treated wood, cedar/natural wood, composite, and PVC. Pressure-treated (PT) wood is the most economical and widely used — it's affordable and structurally strong, but it requires regular maintenance (cleaning, staining/sealing every year or few years) and can warp, crack, or splinter over time, with a typical lifespan of around 15-20 years with upkeep. Cedar and redwood (natural woods) are mid-range — they're attractive, naturally resistant to rot and insects, and a step up in looks from PT, but they also need regular sealing/staining to maintain and weather over time. Composite (wood-plastic composite, like Trex and similar) costs more upfront but is low-maintenance — no staining or sealing, just occasional cleaning — and resists rot, fading, staining, and insects, lasting 25-30+ years with long warranties; it's a popular replacement choice precisely because people are tired of maintaining wood. PVC (fully synthetic/cellular vinyl) is the most expensive but the most durable and lowest-maintenance, fully resistant to moisture, rot, and insects, and lightweight, ideal for harsh or wet climates. The trade-off is upfront cost versus long-term maintenance and lifespan: wood is cheaper now but costs time and money to maintain and replaces sooner; composite and PVC cost more now but save on maintenance and last longer, often making them cost-effective over the deck's life, especially if you'll keep the home a while. Since you're already paying for the labor and demolition of a replacement, upgrading to a longer-lasting material can be a smart time to do it. This calculator lets you compare pressure-treated, cedar/wood, composite, and PVC, with the premium materials priced higher. Consider your budget, how much maintenance you want, your climate, and your timeline in the home.

Whether you need a permit to replace a deck depends on the scope of the work and your local building department's rules, but structural replacements very commonly require one. As a general guide: simply replacing the deck boards (resurfacing) on an existing, unchanged structure — like swapping worn boards for new ones without touching the framing, footings, size, or height — often does not require a permit in many jurisdictions, since it's considered maintenance rather than structural work (though some areas still want one, so check). However, any structural work usually does require a permit: replacing or modifying the framing (joists, beams, posts), the footings, or the ledger connection; changing the deck's size, shape, height, or layout; rebuilding stairs or railings in a way that affects structure; or a full tear-out and rebuild. Because these involve the structural safety of the deck (and decks are a common source of injury when they fail), building departments want to permit and inspect them to ensure they meet current code — including proper footing depth, joist sizing/spacing, ledger attachment and flashing, railing height and baluster spacing, and connection hardware. A key point: even if your old deck was built without a permit or to an older code, a replacement typically must be brought up to current code, which the permit/inspection process enforces (and which can affect the design and cost). Permits usually involve submitting a plan, paying a fee, and passing inspections (often at the footing and framing stages, then a final). Skipping a required permit can cause problems with insurance, home resale (unpermitted structural work is a red flag for buyers and inspectors), and safety, and can result in fines or being required to redo work. This calculator offers a permit and inspection as an add-on; always confirm requirements with your local building department, and a reputable contractor will know and handle the local permitting. For structural deck replacement, getting the permit is both a legal and safety safeguard.

Most deck replacements take from a few days to about two weeks, depending on the scope, the deck's size and height, the material, and factors like permitting and weather. A surface re-deck (replacing just the boards and railing on a sound existing frame) is the fastest — often a few days, since there's no structural or footing work, just removing the old boards and installing new ones plus railing. Replacing the framing as well adds time for tearing out and rebuilding the joists and beams. A full tear-out and rebuild takes the longest, commonly one to two weeks or more, because it includes demolishing and disposing of the entire old deck, possibly removing and pouring new footings (concrete needs time to set), building the new substructure, and then the decking, railing, and stairs — with inspections at key stages. The overall timeline includes more than just the build: if a permit is required, obtaining it can add days or weeks before work starts, and required inspections (often at the footing and framing stages, then final) can pause the work waiting for the inspector. Other factors that extend the schedule: the deck's elevation (working on a second-story or tall deck is slower), the complexity (multiple levels, lots of railing and stairs, intricate patterns), the material (composite/PVC installation is straightforward, but special orders for a specific product or color can delay the start if materials must be ordered), and weather (demolition, concrete work, and building need reasonable conditions). Demolition and disposal of the old deck add time at the front of the project compared to a new build. Your contractor can give a specific schedule after assessing the scope, size, height, material availability, and permitting in your area. This calculator estimates the cost; the timeline depends on these same factors plus permits, inspections, and weather.