Composite deck cost in Washington, DC
Local estimate from BLS wage data and BEA price levels. Reviewed Nov 4, 2026.
- Typical range (300 sq ft)
- $12,300 – $24,700
- Per sq ft
- $41 – $82
- before permit
- Versus US midpoint
- +2%
- US $18,100
- Rank of 300 metros
- #74
- 1 = most expensive
If you want to build a composite deck in Washington, plan on $12,300 to $24,700 for 300 sq ft, all in. Per sq ft, that is $41 to $82 for materials and labor, with the permit on top. The local midpoint lands close to the national one. Building materials run about 5% above the US average here (BEA goods price index 104.8).
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Estimated cost for 300 sq ft in Washington, DC, standard level
$16,000 to $21,000
About $53 to $69.50 per sq ft before permits. Labor is about 59% of the bill.
| Part | Low | High |
|---|---|---|
| Materials | $6,550 | $8,550 |
| Labor | $9,400 | $12,300 |
| Permits and fees | $85 | $130 |
| Total | $16,000 | $21,000 |
Cost breakdown for 300 sq ft in Washington, DC
| Part of the job | Low | Midpoint | High | Share |
|---|---|---|---|---|
| Materials | $5,050 | $7,550 | $10,100 | 41% |
| Labor | $7,250 | $10,800 | $14,500 | 59% |
| Permits and fees | $55 | $110 | $160 | 1% |
| Total | $12,300 | $18,500 | $24,700 | 100% |
Where the Washington price comes from
The wage side of the estimate leans on carpenters, who do 80% of the hours on a typical job. Their local median is $29.23 an hour. Add the other trades involved and the blended wage index for Washington is 1.00 (US = 1.00), which puts labor at 59% of the total.
On the materials line, the BEA goods price index for the Washington metro is 104.8 (US = 100). The midpoint materials bill for 300 sq ft comes to $7,550, compared with $7,200 at national prices. Permit and inspection fees are scaled by the broader index (108.9) and land at $55 to $160.
Optional extras in Washington
Extras are quoted nationally and then scaled to Washington by the average of the local wage index (1.00) and goods index (1.05), a factor of 1.03. Tick any of them in the estimator above to add them to your total. Treat these as planning figures: an add-on touches different trades than the main job, so the scaling is an approximation.
| Add-on | Local range |
|---|---|
| Add a deck railing (approx. 0.3 ft per sq ft) | $1,850 – $5,550 |
Climate in Washington: timing your composite deck job
We use NOAA's 1991-2020 climate normals for Washington Reagan Ap (5 miles from the city center). These are 30-year monthly averages, not forecasts.
August through June is the stretch where exterior installation runs into the fewest weather problems in Washington (11 of 12 months). July has an average daytime high of 90°F or more.
Washington gets about 42 inches of precipitation in a normal year, including roughly 14 inches of snow. The wettest months are May, June and July (4.3 inches in July). Inside the workable window, January and February are the driest, at 2.9 and 2.6 inches. The station averages about 40 days a year at 90°F or above.
Does the season change the price? Probably, but we do not have a sourced seasonal price curve, so the estimator shows a year-round figure and does not adjust by month. When you collect quotes, ask whether scheduling in a slower month gets a better rate.
| Month | Avg high °F | Avg low °F | Precip (in) | For this job |
|---|---|---|---|---|
| Jan | 45 | 30 | 2.9 | Workable |
| Feb | 48 | 32 | 2.6 | Workable |
| Mar | 57 | 39 | 3.5 | Workable |
| Apr | 68 | 48 | 3.2 | Workable |
| May | 77 | 58 | 3.9 | Workable |
| Jun | 85 | 68 | 4.2 | Workable |
| Jul | 90 | 72 | 4.3 | Hot |
| Aug | 88 | 71 | 3.3 | Workable |
| Sep | 81 | 64 | 3.9 | Workable |
| Oct | 69 | 52 | 3.7 | Workable |
| Nov | 58 | 42 | 2.9 | Workable |
| Dec | 49 | 35 | 3.4 | Workable |
Cost by quality level and size in Washington
Three bands are cut from the same cited range and localized for Washington wages and prices. They overlap on purpose: a good standard job and a modest premium job can cost the same. The grid below prices the same bands at 4 common sizes.
Basic
$12,300 to $17,300
Entry-level composite boards, low deck, simple shape
Standard
$16,000 to $21,000
Mid-grade capped boards with railing and stairs
Premium
$19,700 to $24,700
Premium capped or PVC boards, multi-level, hidden fasteners
| Size | Basic | Standard | Premium |
|---|---|---|---|
| 10x12 (120 sq ft) | $4,950 – $6,950 | $6,450 – $8,450 | $7,950 – $9,950 |
| 12x12 (144 sq ft) | $5,950 – $8,350 | $7,750 – $10,100 | $9,550 – $11,900 |
| 16x20 (320 sq ft) | $13,100 – $18,400 | $17,100 – $22,400 | $21,000 – $26,300 |
| 20x20 (400 sq ft) | $16,400 – $23,000 | $21,300 – $27,900 | $26,300 – $32,900 |
Washington against nearby metros and the rest of the District of Columbia
Contractors rarely work more than an hour or two from home, so the neighboring metros set a rough ceiling and floor for your quotes. Midpoints for 300 sq ft range from $16,100 to $18,500 across Washington and its five closest metros.
| Area | Range | Midpoint | vs. here |
|---|---|---|---|
| Washington, DCthis page | $12,300 – $24,700 | $18,500 | |
| Hagerstown, MD55 miles | $11,400 – $22,800 | $17,100 | −8% |
| Baltimore, MD60 miles | $12,300 – $24,700 | $18,500 | level |
| Winchester, VA60 miles | $10,700 – $21,500 | $16,100 | −13% |
| Lexington Park, MD65 miles | $12,200 – $24,500 | $18,300 | −1% |
| Chambersburg, PA75 miles | $10,900 – $21,900 | $16,400 | −11% |
| District of Columbia (statewide) | $12,600 – $25,200 | $18,900 | +2% |
| United States | $12,100 – $24,200 | $18,100 | −2% |
Across 300 US metros, Washington comes in at #74 from the top. The priciest is Honolulu, HI at $25,200; the cheapest is Brownsville, TX at $13,500 (midpoints, 300 sq ft). Statewide, Washington is 2% below the District of Columbia figure.
Washington is the only District of Columbia metro we cover, so the statewide page is the only in-state comparison. It uses statewide wages, which include rural areas.
Cities with a workforce like Washington's
Big cities and small ones price differently, so here is Washington against the 4 metros with the closest total employment.
| Metro | Size | Range | Midpoint | vs. here |
|---|---|---|---|---|
| Houston, TX | 3,289,720 jobs | $10,900 – $21,800 | $16,300 | −12% |
| Philadelphia, PA | 2,897,830 jobs | $12,300 – $24,600 | $18,400 | level |
| Dallas, TX | 4,049,800 jobs | $11,000 – $22,000 | $16,500 | −11% |
| Atlanta, GA | 2,889,670 jobs | $11,000 – $22,000 | $16,500 | −11% |
Planning more than one job in Washington?
Because every project leans on different trades, Washington's wage level does not move all prices equally. Against the US midpoint, gutters runs +4% and paver patio +3%.
| Project | Size | Range | vs. US |
|---|---|---|---|
| Wood deck | 300 sq ft | $7,750 – $15,600 | +3% |
| Concrete patio | 300 sq ft | $1,300 – $4,150 | +4% |
| Paver patio | 300 sq ft | $3,100 – $5,600 | +3% |
| Gutters | 160 linear ft | $1,300 – $4,350 | +4% |
Washington labor market for composite deck
Wages are the part of this estimate that changes most from town to town. 2 trades carry the job here, and each is compared with its US median. The weighted result for Washington is 1.00 times the national level.
For carpenters (47-2031, weighted 80%) the local median is $29.23 an hour, which is in line with the national $29.12. The middle half of them earn between $26.62 and $35.56 an hour. BLS counts 13,280 of them working in the area, 42.3 for every 10,000 jobs (US: 43.1), so the local bench is about average.
Construction laborers (47-2061), 20% of the weighting: a median of $22.80 an hour, in line with the US median of $22.66. The middle half of them earn between $20.07 and $27.05 an hour. About 17,710 work in the metro. That is 56.5 per 10,000 jobs, compared with 70.5 nationally, so expect fewer local crews to bid.
Quotes come from real crews, not medians. If the carpenters on your job are paid at the 75th percentile ($35.56 an hour) instead of the median, the labor line grows by about $1,900. At the 25th percentile ($26.62) it shrinks by about $770. The total moves by 10.1% or 4.2%, so wages alone rarely explain a quote that is far outside our range.
For context on the local economy, BLS counts 3,136,190 jobs in the Washington-Arlington-Alexandria area. That makes it the 6th largest of the 300 metros we cover, with 2.02% of US employment.
| Trade | Weight | 25th pct | Median | 75th pct | US median | Ratio | Level used |
|---|---|---|---|---|---|---|---|
| Carpenters (47-2031) | 80% | $26.62 | $29.23 | $35.56 | $29.12 | 1.00 | metro |
| Construction laborers (47-2061) | 20% | $20.07 | $22.80 | $27.05 | $22.66 | 1.01 | metro |
| Blended | 100% | 1.00 | |||||
Composite deck: what moves the price in Washington
Labor
Labor for composite is $24-$48 per sq ft, higher than wood because the boards need extra parts and more careful assembly.
Drainage
Ground-level decks over poorly draining yards may need $1,000-$4,000 of drainage work first.
Engineering
Large or complex decks may need a structural engineer at $100-$220 an hour to get a permit.
Get 3 local quotes
Tell us about the job and we will try to connect you with up to three local contractors for written quotes. It is free and you are under no obligation to hire. Your estimate of $16,000 to $21,000 for Washington, DC is attached.
A detailed PDF report of this estimate, $9
Multi-page report for Washington, DC: low, typical and high cost, a line-item breakdown of materials and labor by trade, permit notes, the best months to schedule, a quote comparison sheet, red flags, questions for contractors, checklists and every source. Save your estimate above, preview page 1 free, and unlock the full report for $9 one-time, or get every report with CostLocal Pro.
Composite deck in Washington: your questions
+How much does it cost to build a composite deck in Washington?
For 300 sq ft, expect $12,300 to $24,700 in the Washington area. A standard-spec job lands at $16,000 to $21,000. Small jobs usually cost more per sq ft and large ones less.
+What is the price per sq ft for composite deck in Washington?
About $41 to $82 per sq ft for materials and labor, plus $55 to $160 for the permit if one is needed. The US range is $40 to $80.
+Is composite deck cheaper in Washington or Hagerstown?
Hagerstown is 55 miles away. The midpoint for 300 sq ft there is $17,100, which is 8% less than Washington ($18,500). Wage and materials indexes both feed that gap.
+How much of the bill is labor in Washington?
About 59% at the midpoint, or $10,800 out of $18,500. Materials are 41% and permits 1%. Nationally, labor is 60%.
+What would 16x20 (320 sq ft) cost in Washington?
$13,100 to $26,300. Pick a different size in the estimator above to get your own number.
+Does composite deck need a permit in Washington?
Often, but rules are set by your city or county building office, so call before you hire. Budget $55 to $160 for fees in the Washington area (our national range of $50 to $150 scaled by the local price level).
+Is Washington expensive for composite deck compared with the rest of District of Columbia?
Washington is 2% below the District of Columbia statewide estimate ($18,900 at the midpoint).
+What do carpenters earn in Washington?
The BLS median is $29.23 an hour in the Washington area, compared with $29.12 nationally. The 25th to 75th percentile range is $26.62 to $35.56.
+What do basic and premium composite deck work cost in Washington?
For 300 sq ft, basic work runs $12,300 to $17,300 and premium work $19,700 to $24,700. Basic means: entry-level composite boards, low deck, simple shape. Premium means: premium capped or PVC boards, multi-level, hidden fasteners.
+When is the best time to build a composite deck in Washington?
Based on NOAA 1991-2020 normals, the comfortable months for this kind of work are August through June. January and February are typically the driest of those months. Local contractors' schedules matter as much as the weather, so book early for the busy months.
+What does "add a deck railing" add in Washington?
$1,850 to $5,550 for 300 sq ft, from a national range scaled by the local wage and goods indexes.
Composite deck near Washington
Where these numbers come from
Base prices are national ranges from the sources below. We scale labor by local BLS wages, materials by BEA goods prices and permits by the BEA all-items price level. Full method on the methodology page.
- HomeGuide: How Much Does Composite Decking Cost? (2026) (accessed November 4, 2026)
- HomeGuide: 2026 Building Permit Costs | Fees & Cost Calculator (accessed November 4, 2026)
- BLS Occupational Employment and Wage Statistics, May 2025
- BEA Regional Price Parities, 2024
- NOAA NCEI U.S. Climate Normals, 1991-2020