Throughout the year, perhaps the most common question we get from potential clients is “How much per square foot do you charge for a deck?”
Unfortunately, there are so many variables that go into pricing a deck that it’s impossible to answer that question without either underbidding the job or overcharging the customer. It would be great if we could just take the price of an existing 12×20 deck, divide it by 240, and then multiply it by the square footage of the deck you’d like to build. But the calculation is a bit more complicated than that.
When we prepare a quote for a customer, our estimate is heavily influenced by four things:
- Inclusion of Stairs, and
- Site Conditions.
Let’s look at each of these individually and break down the ways they can impact cost.
Excluding more exotic components in custom decks, the two choices for decking material are wood and composite. A good rule of thumb for pricing is that wooden decks cost less in the short run, and composite decks cost less in the long run.
Maintenance is what makes this true. Maintenance on composite decks is relatively simple, while wooden decks require more care, effort, and expense. To properly maintain a wooden deck with rail, it should be power washed annually — by a professional.
We can’t stress the “professional” part of that sentence enough. A pressure washer in the wrong hands can ruin a new wooden deck and incur costly repairs.
To properly power wash a deck, the bulk of the time must be spent cleaning the balusters (sometimes called pickets). This is meticulous work, because balusters are thin, closely spaced, and easily damaged if the pressure washer gets too close. Proper cleaning must be done from a set distance and must be done 4 or 5 times per side to get the baluster truly clean. It’s time-consuming work that few homeowners want to do.
The other component of wooden deck maintenance is staining. High-quality stains are pricey, and low-quality stains don’t look great and won’t last. As with power washing, the largest amount of labor takes place on the balusters — 4 sides, with a brush, by hand. It’s a lot of labor, and labor costs money. Professional staining will cost about $1,200 every two years (minimum). Add that to the power washing charge (a 240-square-foot deck would be about $800—add another $400 for steps and stair rails) and it’s a pretty hefty bill to keep your deck in good shape.
On the other hand, with composite decking and vinyl/aluminum or composite rail, all of these costs disappear. No power washing, no staining, AND your deck still looks new 10 years later. This comes with a higher initial price—approximately 1/3 more than wood—but it leads to substantial cost savings and extends the life of the deck.
Our company uses Trex Transcends decking for most of the composite decks we build. There are many composite decking manufacturers out there, and they all have their selling points, but we find that the Trex Transcends line has the best price, warranty, and color palette.
As a testament to this, of the 300+ Trex Transcends decks we’ve installed, we have never received a call from a client saying that the material failed in any fashion.
We think that speaks volumes.
If you do decide to go with wood over composite, keep in mind that the grade of the wood is essential to its longevity—wood decking should be #1 grade or better. High-grade wood has a tighter grain and fewer knots than low-grade wood. Tighter grain means the stain will penetrate more uniformly, and fewer knots means the overall appearance will be much better. We exclusively use #1 grade wood (or better) for the trafficable areas of our decks, and we use a lot of #1 grade wood when we frame too. The material is straighter and makes the deck more even, with no dips or rises. Overall, a deck with #1 grade wood looks better and will wear better.
The type of rail used can greatly affect the overall cost of the finished deck. Most wooden decks use wooden rail, which is the least expensive option. Composite rail is by far the priciest, and is mostly chosen for aesthetic reasons, because it comes in many colors and has more of a matte finish (as opposed to the shiny vinyl rail).
Vinyl/aluminum rail is the middle ground—it costs more than wooden rail, but it’s very low maintenance. It has a vinyl exterior surrounding an aluminum rod that provides stability and rigidity, and it only needs occasional cleaning with soap and water to keep it in great shape—no power washing or staining. Coupled with an upgraded deck board (like C-Select grade) you can save thousands of dollars in maintenance over wooden rail without the higher ticket cost of composite rail.
The overall size of the deck is a pretty obvious price factor—as deck size increases, the materials and labor needed to build it increase in turn.
Keeping a deck as small as possible can help constrain costs, but we advise clients that a deck should be a minimum of 12 feet deep in order to be truly functional (depth being the distance from the house to the outer edge of the deck).
We give this advice because most people will need 3 feet for a table and 3 feet for 1 chair on each side. With 9 feet occupied by furniture, that leaves 1 ½ feet behind each chair for people to walk or just push away from the table and relax. By contrast, if a deck is 10 feet deep, you only have half a foot of space on either side, and everything feels tight as a result.
Depth increases don’t come without cost increases, of course. In most counties, you can span a 12-foot depth with a 2×8 joist and easily stay within code. But bumping up the depth by only 2 feet (to 14 feet) means that you must use 2×10 joists to remain code-compliant. Believe it or not, moving from a 2x8x12 joist to a 2x10x12 jumps the price from about $11.00 a joist to $21.00 a joist—a pretty steep price increase for a relatively small size increase.
If a deck is built 1-4 feet above grade, the material will cost a little more than if built directly on the ground, but the real price increase comes once you get above 4 feet. This is because the amount of labor increases significantly when work must be done on a ladder. Standing on a ladder and balancing yourself while holding the end of a 20-foot 2×12 (90-125 lbs.) is precarious at best, so work crews have to take more care (and time) to do the same amount of work they would do on the ground. More labor time equals more labor cost, so expect your quote to be higher if you want a high deck.
Stairs are expensive. The materials cost a lot, and so does the labor needed—it takes a good amount of time and skill to cut a set of stair stringers, which are the notched boards that the stair treads are attached to. For a composite deck, the trim board is expensive, as are the hidden fasteners we use to install them. The alternative way of fastening the trim board to the stringers is with staples—but staples are ugly and will eventually rust and stain the trim board. Although they cost more, we use CoreTex screws with all of our composite trim board, both for structural and cosmetic reasons. CoreTex screws won’t loosen over time like nails and staples, and their unique fastening mechanism allows the screw to be easily hidden by a plug that fits snugly over the screw head (and matches the trim board color).
Whenever someone calls for a deck quote, we set up an appointment to meet with them at the site. One of the reasons for this is to get an idea of the conditions we’ll be facing when building the deck.
Most important in this is assessing the accessibility of the site, which will tell us how difficult it will be to get the delivered materials from the street to the deck’s location.
(Remember that we are dealing with large pieces of lumber that weigh quite a bit.) A townhouse in the middle of a row means a long walk from the front to the back—add a slope and that walk takes even longer.
Even more time consuming is getting an 8-foot ladder stable on severe incline. It’s tricky and may involve blocking one or more of the ladder legs. Because stability is paramount when setting up ladders, our work crews have to take more time to make sure no one gets hurt.
As you can see, the cost of a deck is not a straightforward equation. We work very hard to get you the best possible price by minimizing waste, optimizing our labor, and prioritizing quality while building a deck that will be the envy of your neighborhood. Deck Envy. It’s a real thing. Let us help your neighbors get there.