The first cost question most St. Louis homeowners actually need answered isn't what a new deck costs. It's whether the deck they already have is worth saving, because that one decision moves the final number by thousands of dollars in either direction. Below is how the repair-versus-rebuild math actually works, followed by what a new deck runs by size and material, what pushes the price up or down, and a table you can use as a starting point before you call (314) 626-3663 for a number based on your actual yard.
Almost always cheaper to repair, right up until it isn't, and the line between those two is narrower than most homeowners think. A handful of soft boards, a wiggly rail, or a step that needs re-securing is a repair, and it often runs a few hundred dollars to a bit over a thousand depending on how much has to come apart to get at the problem. Once the damage moves into the frame, a ledger board pulling away from the house, joists that flex in more than one spot, posts rotted below the collar, the math changes fast. Rebuilding a compromised frame properly can run half to two-thirds of what a full replacement costs, and at the end of it you still have an old deck's layout, an old deck's footings, and whatever design compromises got made twenty years ago. A lot of homeowners spend repair money three or four separate times on the same failing deck before anyone adds it up and realizes a rebuild would have been cheaper the second time around.
It comes down to the frame and the footings, not the surface. Boards, balusters, and stair treads are the easy, cheap part to fix because they don't carry structural responsibility beyond their own weight. The ledger board is a different story: it's bolted to the house and carries a big share of the deck's total load, and if it's separating from the rim joist or showing rot at the bolts, that's not cosmetic. Footings that were poured shallower than local frost depth requirements move every winter, a little at a time, and no amount of surface repair stops that movement. A contractor worth hiring checks these three things first, the ledger connection, the footings, and joist condition, before ever talking about which boards need replacing, because those three answer the repair-or-rebuild question by themselves.
Not sure which side of that line your deck is on? Call (314) 626-3663 for a free on-site look before you spend money either direction.
Size drives cost roughly in a straight line, though not perfectly, since small decks still carry fixed costs like permitting and a crew's minimum trip charge that don't scale down with square footage. A modest 10 by 12 deck sits at the low end of most budgets and works fine for a grill and a small table. A 14 by 16 or similar mid-size deck, the size a lot of St. Louis families land on, costs more in materials and framing time but still tends to be a single-level, single-weekend-crew job. Anything past around 300 square feet, or any design that steps down a slope in two or three levels, starts adding cost for extra framing, extra footings, and often extra stairs, faster than the square footage alone would suggest.
Material is usually the second-biggest lever after size, and it's the one homeowners have the most control over. Pressure-treated pine costs the least up front and is what most St. Louis decks built before the 2010s are made of, but it demands a real maintenance schedule and has the shortest lifespan of the common options. Cedar costs more than pine, resists rot and insects on its own, and looks better without staining, though it still needs regular sealing to hold up through freeze-thaw winters. Composite skips almost all of the yearly upkeep and handles this region's humidity and temperature swings better than wood, at a noticeably higher material cost. PVC and premium composite sit at the top of the range and are built for homeowners who want to never think about the deck surface again once it's installed.
Beyond size and material, a handful of factors swing a quote more than people expect going in.
| Material | Typical Installed Cost | What You're Trading Off |
|---|---|---|
| Pressure-treated pine | $25 to $40 per square foot | Lowest upfront cost, but needs staining or sealing on a regular schedule and has the shortest lifespan of the group |
| Cedar | $30 to $50 per square foot | Natural resistance to rot and insects and a better look than pine, still needs regular sealing |
| Composite | $45 to $70 per square foot | Little to no yearly maintenance and better performance through freeze-thaw and humidity, higher material cost |
| PVC or premium composite | $60 to $85 per square foot | Longest lifespan and least maintenance of the group, priced accordingly |
Treat those ranges as a starting point, not a quote. They cover installed cost, meaning materials and labor together, but they don't account for height, demolition, difficult access, or a design with multiple levels, all of which can push a project above the range for its material tier. The only number that means anything for your specific project comes from someone standing in your yard.
In most of St. Louis County and the city, yes, especially if the deck attaches to the house or sits above a certain height, though the exact threshold and paperwork depend on which municipality your property is in. A deck permit in one St. Louis County city doesn't necessarily follow the same rules as one two towns over. A local contractor should already know the requirements for your address and typically pulls the permit as part of the job rather than leaving it to you.
Generally yes, though how much depends on your local market and how the new deck compares to others in the neighborhood. Remodeling industry cost-value reports have tracked deck projects for years, and decks, composite ones especially, consistently rank among the better-performing home improvements for recouping their cost at resale. No contractor can promise you an exact return, since that depends on your buyer pool and the market when you eventually sell.
Materials cost less if you buy them yourself, but the parts most people underestimate, framing to code, footing depth, and ledger attachment on a house that may be brick rather than siding, are where a DIY build tends to go wrong or take far longer than planned. A failed inspection or a ledger pulling away from the house in year two ends up costing more than hiring it out from the start. A simple ground-level deck is a reasonable DIY project if you're comfortable with framing and permitting. Anything elevated, attached to brick, or built in multiple levels is where most homeowners bring in a contractor instead.
A straightforward ground-level deck often takes a few days to about a week once material is on site. Elevated decks, multi-level designs, or anything requiring a permit inspection between the framing and decking stages take longer, sometimes two to three weeks, particularly if the inspector's schedule adds a few days of waiting in the middle. Weather plays a role too, since a wet St. Louis spring can push a build back by days that have nothing to do with the crew.
Usually not, if the damage comes from age, rot, or normal wear, since insurers treat that as a maintenance issue rather than a covered loss. Coverage is more likely if a specific event caused the damage, a fallen tree limb, a storm, a fire, but that depends entirely on your policy's language and how your insurer reads the cause. Check with your agent before assuming either way, and get a written estimate regardless so you have documentation on hand if you do end up filing a claim.
Get a real number instead of a range. Call (314) 626-3663 for a free, written estimate on your deck project, repair or rebuild, anywhere in the St. Louis area.