Most Knoxville deck projects land somewhere between $8,000 for a simple pressure-treated platform and $80,000 for a full composite deck stepping down a steep lake lot with a screened porch attached. That range is wide on purpose, because the deck itself matters less than the package around it: size, material, railings, how many levels, and how much grading your lot needs before a single footing goes in. Instead of leading with a per-square-foot number that falls apart the moment your yard has a slope in it, here is what Knoxville decks actually cost, organized by the kind of project homeowners actually ask for.
Almost every call we get falls into one of five rough categories. Your project will not match one exactly, but it will land closer to one of these than to a generic per-square-foot formula.
A ground-level or low pressure-treated deck, usually 200 to 300 square feet, with a basic wood railing and one set of stairs. This is the entry point for a straightforward rectangular deck off the back of the house on a lot that does not need much grading. Most of the cost is lumber, framing labor, and footings, without the extras that push a project into the next tier.
Somewhere around 300 to 450 square feet, often with an upgraded railing (aluminum balusters or a mix of wood and composite), a wider stair run, and sometimes a second small landing. This is the size most families settle on for a deck that fits a full patio set, a grill, and room to actually walk around both.
A larger deck, 450 to 650 square feet, built entirely in capped composite decking with hidden fasteners, a premium railing system (cable or aluminum), and often a built-in bench, planter, or lighting package. This tier is popular with homeowners who host, including a fair number of people planning around football season who want a deck that holds a real crowd without every board needing attention every spring.
An engineered, multi-tier deck stepping down a graded or sloped lot, common on property backing up to Fort Loudoun Lake, Tellico Lake, or a Smokies view lot with real elevation change. Expect extra stair runs, footings that go deeper to reach stable soil below the red clay, and sometimes a stamped engineering plan required before Knox County or the City of Knoxville will issue a permit. The drop in your yard, more than the square footage, decides where in this range a project lands.
A deck combined with a screened porch or a pergola or patio cover on top of a base deck build. Because the roof, screening, or shade structure ties into the existing framing and often the house roofline, this is priced as an addition to whichever base package you are already building, not as a separate project from scratch.
Not sure which package fits your yard? Call (865) 909-7677 and describe what you are picturing. We will connect you with a local builder for a free, written estimate based on your actual lot, not a national average.
Package size gets you in the right neighborhood. Material choice moves you around within it.
Pressure-treated pine is the baseline for a reason: it is the least expensive decking material that still holds up structurally, and it is what most framing lumber is regardless of what goes on top. It needs staining or sealing every two to three years to actually hold up in Tennessee sun and humidity, which is a real ongoing cost most homeowners forget to budget for until year three. Cedar costs noticeably more than pressure-treated pine and has a nicer natural grain, but it still needs the same kind of upkeep. Capped composite, the Trex and TimberTech style products most homeowners mean when they say "composite," costs more upfront than either wood option but needs no staining, no sealing, and holds its color far longer in direct sun. Premium PVC decking sits at the top of the material range, costs the most per board, and handles moisture even better than composite because it contains no wood fiber at all to absorb it.
Railings move the number too, sometimes more than homeowners expect. A basic wood baluster railing is the cheapest option. Aluminum balusters cost more but need zero maintenance. Cable railing, popular on lake-view decks because it does not block the view, costs noticeably more than either due to the hardware and tensioning labor. Glass panel railing sits at the top of the range and shows up mostly on higher-end composite builds.
Two decks that sound identical on the phone can price out thousands of dollars apart once a builder actually walks the lot. A few things explain most of the gap.
| Package | Typical Size | Materials | Price Range | Best For |
|---|---|---|---|---|
| Simple Platform | 200 to 300 sq ft | Pressure-treated pine, wood rail | $8,000 to $14,000 | Flat lots, basic outdoor space |
| Everyday Family Deck | 300 to 450 sq ft | PT pine or cedar, upgraded rail | $16,000 to $26,000 | Most single-family homes |
| Composite Entertainer | 450 to 650 sq ft | Capped composite, cable or aluminum rail | $32,000 to $50,000 | Frequent hosting, low upkeep |
| Lake-Lot / Multi-Level | Varies with slope | Composite or premium wood, engineered framing | $45,000 to $80,000+ | Sloped, lake, or view lots |
| Deck-Plus (porch or pergola) | Base deck plus addition | Depends on base package | +$15,000 to $40,000+ | Extending usable season |
These are ranges, not quotes. Lumber and composite pricing shift with the market, and your actual number depends on the specifics a phone call cannot capture. Treat the table as a starting point for a conversation, not a ceiling or a floor.
Knoxville has more sloped and lake-adjacent lots than a lot of the metro markets these national cost guides are written for, so the averages you find online tend to run low for a big share of local projects. Red clay swells and dries unevenly across a sloped yard, which means footings need to go past the frost line and into stable soil, sometimes considerably deeper on the downhill side of a lot than the uphill side. A deck that steps down toward Fort Loudoun Lake or Norris Lake also needs more linear feet of framing per square foot of usable deck than a flat-lot build, since a chunk of the structure is stairs and support rather than open floor. If your property sits near TVA reservoir shoreline, there can also be shoreline permitting considerations on top of the standard county process, which a local builder will already know how to navigate.
Depends on how long you plan to own the house and how much you value not staining a deck every other spring. Remodeling magazine's annual Cost vs. Value report has tracked wood deck additions recouping a solid share of their cost at resale for years running, with composite trailing slightly behind on pure resale percentage despite its higher sticker price. What that comparison leaves out is the maintenance math: a wood deck that needs sealing every two to three years costs real money and real weekends over a fifteen-year span, and a lot of homeowners decide the composite premium is really just prepaid maintenance. If you are planning to sell within a couple of years, a well-built wood deck is usually the more efficient dollar. If you are staying, composite tends to win the longer math.
Most attached decks in Knox County and the City of Knoxville need a building permit, and that fee is typically a small piece of the total project cost. The bigger cost driver is engineering, which only kicks in for tall, multi-level, or structurally unusual decks. A straightforward ground-level deck rarely needs a stamped engineering plan.
It depends on size and how the old deck was built. A small deck on surface footings comes out relatively cheaply. A larger deck with posts set deep in concrete, or one attached to the house in a way that needs careful work to avoid damaging siding, costs more to remove. Most builders fold this into the overall project quote rather than pricing it as a separate line item.
Over ten to fifteen years, often yes, once you account for the staining and sealing a wood deck needs every two to three years in this climate. The upfront gap is real and composite costs more on day one. Whether it pencils out depends on how long you keep the house and how much you would otherwise spend on maintenance.
Usually because "the same deck" is not actually the same once someone measures the lot. Slope, soil access, the exact footing depth required, and whether a stamped engineering plan is needed can all differ between two houses on the same street. A written estimate after an actual site visit is the only number worth comparing.
Both matter, but height changes the structural requirements in ways square footage alone does not. A tall deck needs code-compliant guards, deeper footings, and often a more involved stair design, so two decks of the same square footage can price differently if one sits three feet off the ground and the other sits ten.
Ready for a real number instead of a range? Call (865) 909-7677 for a free, on-site estimate from a licensed Knoxville deck builder who can measure your actual lot.