How much a 12×16 deck costs in 2026: pressure-treated vs composite, line by line

The 12×16 deck this estimate prices

A cost per square foot means nothing without the deck behind it, so here is the one priced. It runs 16 ft along the back wall of the house and projects 12 ft into the yard, 192 sq ft of surface. The walking surface sits 36 in. above grade. It hangs off a ledger bolted to the house band joist. One stair, 36 in. wide, comes down the middle of the long side. A wood guard runs along the three open sides.

Height matters more than it looks. The 2021 IRC requires a guard wherever the walking surface is more than 30 in. above grade within 36 in. of the edge, so at 36 in. this deck needs one. On this deck the guard is $413.52 of material and 7 crew-hours. Drop the same deck to 24 in. and that whole line disappears, along with one riser.

I assumed a 36 in. frost depth. Ask your building department for yours; it changes the concrete.

This page prices the deck. The build itself, stage by stage with the inspector's check for each, is in the guide on how to build a deck step by step.

Framing takeoff from DCA 6

DCA 6 is the American Wood Council's prescriptive deck guide, written to match the International Residential Code for single-level decks that stay inside its limits. It assumes a 40 psf live load, No. 2 lumber and wet service. Everything below is for southern pine, the species the treated lumber at the store is cut from.

Joists

Table 2 allows a 2x8 at 16 in. on center a span of 11 ft 10 in. The deck projects 12 ft, so a beam at the outer edge would ask a 2x8 for more than it has. Move the beam in instead. With the beam 10 ft 6 in. from the ledger, the joists span 10 ft 6 in. and cantilever about 1 ft 1-1/2 in. past a 3 in. wide beam to a rim joist. DCA 6 caps the overhang at the lesser of 2 ft (its table value for this size) and a quarter of the span, so this fits with room to spare. Thirteen joists at 16 in. cover 16 ft: 192 in. divided by 16 is 12 bays, and 12 bays need 13 joists.

Beam and posts

Table 3A lets a two-ply 2x10 span 7 ft 1 in. when the joists it carries span up to 12 ft. Three 6x6 posts set 1 ft in from each end and one in the middle give two 7 ft beam spans, and the 1 ft ends are inside the quarter-span overhang the guide allows. The post tops are notched for the beam and through-bolted with two 1/2 in. bolts each, one of the attachments DCA 6 draws. DCA 6 measures post height from the top of the footing to the underside of the beam, about 16 in. here, so the 2 ft height at which it starts asking for diagonal bracing on corner posts is never reached.

Footings

Table 4, at a beam span up to 8 ft and a joist span up to 14 ft, calls for a 24 in. round footing 10 in. thick on 1,500 psf soil. With the bottom at 36 in., each post gets a 24 × 10 in. pad (2.618 cu ft) and a 12 in. tube pier from the pad to 2 in. above grade (1.833 cu ft), or 4.451 cu ft each. The stair lands on two 4x4 posts in 12 in. tubes poured the full 38 in. (2.487 cu ft each). That totals 18.33 cu ft. At the 0.45 cu ft Quikrete lists for a 60 lb bag, it is 41 bags. The concrete calculator does the same volume math for any footing size.

Ledger and flashing

A 2x8x16 ledger with 1/2 in. lag screws. DCA 6 Table 5 sets the spacing by joist span, and for 10 ft 1 in. to 12 ft into a 1-1/2 in. lumber band joist it is 15 in. on center, staggered. Across 192 in. that is 13 spaces and 14 lags. The siding comes off behind the ledger and flashing goes in first; DCA 6 requires corrosion-resistant flashing at any ledger on a wood-framed wall. It also requires lateral hold-downs at two points within 2 ft of the deck ends, rated at least 1,500 lb each.

Connectors

One hanger per joist at the ledger and one tie per joist at the beam, 13 each, plus blocking between joists over the beam. DCA 6 wants connectors in treated lumber galvanized to G185 or stainless, which is why the hangers, ties and post bases priced here are MiTek's triple-zinc parts. Two items need a second look at the store: the holdown I found is G90, a lighter coating than G185, and the 1/2 in. lag screws are listed as galvanized without saying hot-dipped. Ask for the heavier coating on both.

The deck cost calculator on this site returns the same 13 joists, 26 rows of pressure-treated boards and 351 composite clip points for these dimensions. It counts 8 posts, though, because it assumes a freestanding grid with a post line under each edge. On an attached deck the ledger carries the house side, so that line needs no posts, and DCA 6 lets the beam run past its end posts. Three is right for this layout.

Decking, stairs and guard

The pressure-treated surface is 5/4 decking, 1-5/32 × 5-1/2 in., laid parallel to the house with the roughly 1/8 in. gap DCA 6 describes. Twenty-six rows cover 12 ft, since 26 boards and 25 gaps lay out at 146.1 in., just past the 144 in. frame. The last row either hangs about 2 in. over the rim or gets ripped. With 16 ft boards that is 26 boards, plus 10% waste rounded up to 3, so 29.

The composite is UltraDeck Triumph, a capped board sold at Menards with a 25-year limited warranty. Its boards are 5-3/16 in. wide and the clips set a 1/4 in. gap, so 27 rows are needed and you buy 30. The installation guide allows joists at 16 in. for boards laid square to them, so the framing is identical. Each board-to-joist crossing takes one hidden clip: 27 × 13 = 351, or four boxes of 90.

The stair is where the two materials part ways. A 36 in. rise at the IRC maximum riser of 7-3/4 in. needs five risers of 7.2 in. and four treads, each at least 10 in. deep. DCA 6 accepts three cut 2x12 stringers for a 36 in. stair. UltraDeck requires stringers at 8 in. on center under its treads and does not allow grooved boards there, so the composite stair needs six stringers and solid radius-edge boards. The stair calculator works out riser and tread splits for other heights.

The guard runs 12 + 16 + 12 = 40 ft, less a 3 ft stair opening: 37 ft. With posts no more than 6 ft apart (my layout choice), that is ten 4x4 posts, plus two short ones at the stair foot for the handrail. The IRC sets the guard at 36 in. minimum with openings that stop a 4 in. sphere, so 2x2 spindles at 5 in. on center (1-1/2 in. of wood, 3-1/2 in. of air) need 444 in. ÷ 5 = 88.8, or 89. Five risers means a handrail on one side. DCA 6 wants each guard post on the rim held down with an anchor rated for at least 1,800 lb; I priced six MiTek holdowns at $28.78, and you should confirm the rated load of whatever you buy.

Line-by-line cost

Material quantities from the takeoff, times the Menards shelf price on September 19, 2026:

As a sanity check, Menards' own 16 × 12 "Florence" material list, with CedarTone boards and a wood railing, shows an approximate price of $3,244.85. CedarTone is the store's pricier prefinished treated line, so landing below it with green-treated boards is what you would expect.

Now the contractor version:

Sales tax and delivery are left out because I could not put a sourced number on them. Disposal on a new deck is scraps and siding offcuts, and it sits inside the contingency.

For a secondary comparison, the 2025 Cost vs Value report prices a 16×20 deck with a built-in bench, planter and a three-step stair at $18,263 nationally in wood and $25,096 in composite, or $57.07 and $78.43 per sq ft. It is a bigger deck with more trim, and an aggregator's national average, so I use it only to check that this estimate is not wildly off.

Labor is 58.6% of the subtotal on the pressure-treated deck. The decking itself, the part people argue about, is 22.5% of the materials and about 7% of the finished price.

Labor: the hours behind the number

I found no public per-square-foot deck labor rate I would build on, so this one comes from two public numbers and one estimate. The BLS May 2025 mean wage is $31.55 an hour for carpenters and $25.02 for construction laborers. Wages are not what an employer pays, though. BLS employer-cost data for the construction industry in June 2026 puts total compensation at $51.96 an hour against $36.13 in wages, a ratio of 1.438 that covers payroll taxes, insurance and benefits. A two-person crew therefore costs ($31.55 + $25.02) × 1.438 = $81.36 an hour. Add 30% for the truck, tools, liability insurance, office and profit, and it bills at $105.77.

The hours are my estimate by task, for a two-person crew. Replace them with a contractor's:

Composite takes longer because 351 clips go in one at a time and the stair has twice the stringers. The guard takes as many hours as the decking or more on both versions, so a bid that prices railing "per square foot of deck" deserves a question.

Low, typical and high

Going from Triumph at $2.35 per linear foot to Inspire at $5.83 adds $1,670.40 of boards before markup. Building it yourself saves $5,203.55 against the typical PT price, almost all of it labor, overhead and contingency.

What the same deck costs in seven states

Lumber prices move a little from state to state. Carpenter wages move a lot. Scaling the crew cost by each state's mean carpenter wage relative to the national $31.55, and holding materials and the permit fixed:

The spread between Mississippi and Illinois is $2,202 on the same drawing. That is larger than the $1,377 it costs to switch the whole surface to composite. A Chicago-area quote well above a national "cost per square foot" figure may simply reflect wages. BLS publishes the same wage for metro areas too, and that is the better number if you live in or near a large city.

Permit fees in two real jurisdictions

Fees are set locally and follow different logic. Montgomery County, Maryland charges a flat $223.87 for an open, unenclosed deck of 500 sq ft or less in fiscal 2027, which is what the table above uses. Rochester, Michigan prices a deck as a residential addition from its construction value: a $40 administration fee, $135 for the first $5,000, $7 for each $1,000 after that, plus a plan review of 0.2% of value with a $150 minimum. On the $7,939.91 PT deck that is $40 + $135 + 3 × $7 = $196, plus $150 of plan review, or $346.

That is 2.8% and 4.4% of the PT job. Skipping it costs more: Rochester charges a $100 stop-work fee and 150% of the normal permit for work done without one. The IRC exemption for small decks requires a deck to be detached and no more than 30 in. up, so it does not apply here.

Pressure-treated vs composite over 20 years

The composite premium on this deck, contractor-built, is $9,316.46 minus $7,939.91: $1,376.55. What buys it back is the maintenance the wood needs and the composite skips. Both need washing, so washing is left out of both.

A restain cycle on the wood covers the deck (192 sq ft), the treads (about 11 sq ft) and both faces of the guard (37 ft × 3 ft × 2 = 222 sq ft), about 425 sq ft. Two coats at 225 sq ft per gallon, the middle of the 100 to 350 range on Sherwin-Williams' SuperDeck data sheet, is 3.8 gallons, so four. At $48.98 a gallon plus a $16.99 jug of cleaner, the materials are $212.91. Paying a painter for two days of two-person work (16 hours at the BLS painter mean of $26.64, loaded 1.438 and marked up 30%, $49.81 an hour) plus the materials with a 10% markup brings a hired cycle to $1,031.09. Consumer Reports puts semi-transparent stain on a two to three year cycle. The deck calculator defaults to two, and so does the base case here.

Money spent in year 10 is worth less than money spent today, so each restain is discounted to present value. I used two rates. The 10-year Treasury yield on September 17, 2026 was 4.94%, a fair stand-in for what cash sitting in safe investments earns. The 8.25% HELOC rate below is the cost if you borrowed.

If you will pay someone to restain, buy the composite. The premium is gone by the second paid cycle, and at 8.25% it still pays back in year 4. If you will do it yourself and can keep to a two-year schedule, the wood deck stays cheaper for 24 years. At 8.25% the DIY case never pays back at all. The premium composite changes this arithmetic: its premium over PT, with markup and contingency, is $3,397.73, and even hired restains take until year 10 to cover it.

Stain prices were held flat, which flatters the wood if they rise. Board replacement on an aging wood deck was left out because I found no source I would put a number on.

Paying for it with a HELOC

The prime rate rose to 7.00% on September 17, 2026. SchoolsFirst Federal Credit Union's rate sheet dated September 19 prices its standard HELOC at prime minus 0.50 to prime plus 3.00, so 6.50% to 10.00%. I used the midpoint, 8.25%.

Stretching the payoff from five years to ten more than doubles the interest, so set the payment to clear the balance in five years whatever the minimum allows. The rate floats with prime, which just moved up. The HELOC calculator shows the payment during the draw period and after it converts.

Where the budget blows up

The house side, first. DCA 6 lets you hang a ledger only from a solid band joist at least 1 in. thick, and forbids attaching through brick veneer, to a cantilevered floor or to a 2x4 truss ribbon. When the siding comes off and the band is one of those, the deck needs a second beam and three more footings at the house. At the prices here that is $421.73 of beam lumber, post, post bases, concrete and tubes, before the labor to dig three more holes. Rot in the band joist behind an old deck is a carpentry job on the house before the deck starts.

Frost depth is next. At 48 in. instead of 36 in., the same five footings take 22.25 cu ft, 50 bags instead of 41. That is only $43.65 of concrete, but hitting rock or a root mat at 30 in. is hours of digging nobody priced. Call 811 before anyone digs, as DCA 6 tells you to.

Changes after framing cost the most, because they touch parts already built. Premium composite also brings its own fascia and matching railing, none of which is priced here.

The last is the one that does not show up for years: an unflashed ledger. Water gets behind it, the house band joist rots, and the lags holding the house side of the deck lose their grip. The flashing on this list costs $40.69. Don't let anyone skip it.

How to check a contractor's quote

Ask for the bid with materials and labor on separate lines. A single number cannot be compared to anything, and a split can be compared to this page. If the material line for a pressure-treated 12×16 comes in far below about $2,500 at these prices, something on the takeoff is missing.

Then read the specification, since that is where a cheap bid hides. It should name joist size and spacing (2x8 at 16 in. for this layout), beam size and post count, footing diameter and depth, the ledger fastener and spacing (1/2 in. lags at 15 in. here), flashing, hangers, the two lateral hold-downs, how guard posts are attached, and stringer count. Ask whether the permit and inspections are in the price and who pulls them. Ask how a rotten band joist or a buried obstruction would be handled and priced, before either one shows up.

Compare the labor line to the hours above at your state's wage. Illinois wages alone put labor 22% over the national figure; the same markup in Mississippi needs an explanation. When you have the bid, put its numbers into the deck cost calculator to see its material count next to the labor share.