Composite deck cost in Illinois
Statewide estimate from BLS wages and BEA prices. Reviewed Nov 4, 2026.
- Statewide range (300 sq ft)
- $14,400 – $28,900
- Per sq ft
- $48 – $95.50
- before permit
- Versus US midpoint
- +19%
- US $18,100
- Metros covered
- 6
Across Illinois, a composite deck costs about $14,400 to $28,900 for 300 sq ft. Statewide, that midpoint is 19% above the US figure of $18,100. Carpenters earn a median $37.98 an hour in Illinois (US: $29.12).
Inside Illinois, the metros we cover range from $19,100 (Champaign) to $22,100 (Chicago) at the midpoint. Pick your closest city in the table for a tighter number.
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Estimated cost for 300 sq ft in Illinois (statewide), standard level
$18,700 to $24,500
About $62 to $81.50 per sq ft before permits. Labor is about 65% of the bill.
| Part | Low | High |
|---|---|---|
| Materials | $6,500 | $8,450 |
| Labor | $12,200 | $15,900 |
| Permits and fees | $80 | $120 |
| Total | $18,700 | $24,500 |
Cost breakdown for 300 sq ft in Illinois
| Part of the job | Low | Midpoint | High | Share |
|---|---|---|---|---|
| Materials | $5,000 | $7,500 | $9,950 | 35% |
| Labor | $9,350 | $14,100 | $18,700 | 65% |
| Permits and fees | $50 | $100 | $150 | 0% |
| Total | $14,400 | $21,600 | $28,900 | 100% |
If you are planning more than one job in Illinois
Each project weights the trades differently, so Illinois's wage level does not push every price by the same amount. Compared with the US midpoint, concrete patio is +20% and wood deck +15%.
| Project | Size | Range | vs. US |
|---|---|---|---|
| Wood deck | 300 sq ft | $8,700 – $17,500 | +15% |
| Concrete patio | 300 sq ft | $1,450 – $4,850 | +20% |
| Paver patio | 300 sq ft | $3,600 – $6,500 | +20% |
| Gutters | 160 linear ft | $1,550 – $4,850 | +16% |
Illinois metro-by-metro prices
1 of the 6 metros sit above the statewide midpoint of $21,600, and the top-to-bottom gap is 16%. Each row prices the default size with that metro's own BLS wages and BEA price levels, so the gap between rows is real local variation rather than a flat markup.
| Metro | Range (300 sq ft) | Midpoint | vs. state |
|---|---|---|---|
| Chicago, IL | $14,700 – $29,500 | $22,100 | +2% |
| Springfield, IL | $13,700 – $27,500 | $20,600 | −5% |
| Peoria, IL | $13,600 – $27,300 | $20,500 | −5% |
| Bloomington, IL | $13,600 – $27,200 | $20,400 | −6% |
| Rockford, IL | $13,200 – $26,500 | $19,900 | −8% |
| Champaign, IL | $12,700 – $25,500 | $19,100 | −12% |
Why two Illinois quotes can differ
Board grade
Composite materials run $16-$32 per sq ft and the installed price is $40-$80 per sq ft, including the substructure (HomeGuide).
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.
Weather windows across Illinois
Weather decides when exterior installation can happen, and Illinois is not uniform. The table uses NOAA's 1991-2020 climate normals from the weather station nearest each metro we cover, and counts the months that are neither cold nor hot enough to complicate the job.
Every Illinois metro on the list has 9 comfortable months, though rainfall ranges from 34 inches a year in Chicago to 40 in Springfield.
We do not adjust prices by month, because we have no reliable published data on seasonal pricing. Timing is still worth raising when you collect bids.
| Metro | Jan avg low °F | Jul avg high °F | Precip (in/yr) | Comfortable months |
|---|---|---|---|---|
| Chicago | 19 | 85 | 34 | 9: March through November |
| Peoria | 18 | 86 | 38 | 9: March through November |
| Rockford | 15 | 84 | 37 | 9: March through November |
| Champaign | 18 | 85 | 37 | 9: March through November |
| Springfield | 19 | 86 | 40 | 9: March through November |
| Bloomington | 16 | 86 | 39 | 9: March through November |
Illinois labor market for composite deck
Illinois's labor line is priced from 2 trades, each compared with its US median wage. After weighting by each trade's share of the work, the state comes out at 1.30 times the national level.
Carpenters (47-2031), 80% of the weighting: a median of $37.98 an hour, 30% above the US median of $29.12. The middle half of them earn between $27.00 and $51.42 an hour. About 19,570 work in the state. That is 32.1 per 10,000 jobs, compared with 43.1 nationally, so expect fewer local crews to bid.
For construction laborers (47-2061, weighted 20%) the local median is $29.18 an hour, which is 29% above the national $22.66. The middle half of them earn between $22.14 and $45.79 an hour. BLS counts 35,940 of them working in the state, 58.9 for every 10,000 jobs (US: 70.5), so the local bench is thinner than average.
A crew paid at the 75th percentile for carpenters ($51.42 an hour) would add about $4,000 to the statewide midpoint; one at the 25th percentile ($27.00) would take off about $3,250. Use that as a rough guide to how far a bid can sit from our midpoint on wages alone.
BLS counts 6,098,130 jobs across Illinois (May 2025), which is 3.9% of US employment.
| Trade | Weight | 25th pct | Median | 75th pct | US median | Ratio | Level used |
|---|---|---|---|---|---|---|---|
| Carpenters (47-2031) | 80% | $27.00 | $37.98 | $51.42 | $29.12 | 1.30 | state |
| Construction laborers (47-2061) | 20% | $22.14 | $29.18 | $45.79 | $22.66 | 1.29 | state |
| Blended | 100% | 1.30 | |||||
Illinois against its neighbors
Illinois ranks 2 of 51 (the 50 states plus DC) for composite deck, where 1 is the most expensive. The costliest is Hawaii at $23,800 and the cheapest Oklahoma at $15,300, both for 300 sq ft at the midpoint. Illinois sits at $21,600. The five states closest by workforce center are listed below.
| State | Distance | Range | Midpoint | vs. here |
|---|---|---|---|---|
| Wisconsin | 120 miles away | $12,200 – $24,400 | $18,300 | −16% |
| Indiana | 140 miles away | $12,100 – $24,300 | $18,200 | −16% |
| Michigan | 220 miles away | $12,000 – $24,100 | $18,100 | −16% |
| Iowa | 240 miles away | $11,500 – $23,100 | $17,300 | −20% |
| Kentucky | 280 miles away | $11,100 – $22,200 | $16,600 | −23% |
Optional extras in Illinois
Add-ons start from national price ranges and are scaled by 1.17 for Illinois, which is the average of the area's wage index (1.30) and goods price index (1.04). The estimator above can add them to your total.
| Add-on | Local range |
|---|---|
| Add a deck railing (approx. 0.3 ft per sq ft) | $2,100 – $6,300 |
Basic, standard or premium: Illinois prices
Bands overlap on purpose, since a good standard job can cost as much as a light premium one. Below are the three bands for the default size, then a grid from 10x12 (120 sq ft) to 20x20 (400 sq ft).
Basic
$14,400 to $20,200
Entry-level composite boards, low deck, simple shape
Standard
$18,700 to $24,500
Mid-grade capped boards with railing and stairs
Premium
$23,100 to $28,900
Premium capped or PVC boards, multi-level, hidden fasteners
| Size | Basic | Standard | Premium |
|---|---|---|---|
| 10x12 (120 sq ft) | $5,800 – $8,150 | $7,550 – $9,900 | $9,300 – $11,600 |
| 12x12 (144 sq ft) | $6,950 – $9,750 | $9,050 – $11,800 | $11,100 – $13,900 |
| 16x20 (320 sq ft) | $15,400 – $21,500 | $20,000 – $26,100 | $24,600 – $30,800 |
| 20x20 (400 sq ft) | $19,200 – $26,900 | $25,000 – $32,600 | $30,700 – $38,400 |
Get 3 local quotes
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Composite deck in Illinois: your questions
+How much does it cost to build a composite deck in Illinois?
$14,400 to $28,900 for 300 sq ft, using statewide wages and prices. Metro areas inside Illinois can sit above or below that.
+Which city in Illinois is cheapest for composite deck?
Champaign at about $19,100 (midpoint, 300 sq ft). The priciest is Chicago at $22,100.
+Is composite deck cheaper in Illinois than the US average?
It is 19% more expensive: $21,600 against $18,100 for 300 sq ft at the midpoint.
+What share of the price is labor in Illinois?
About 65% ($14,100). Materials are 35%. Statewide labor for this job is weighted 1.30x the national wage level.
+What do carpenters earn in Illinois?
The BLS statewide median is $37.98 an hour, against $29.12 for the US. The 25th to 75th percentile range is $27.00 to $51.42.
+Where does Illinois rank for composite deck costs?
2nd most expensive of 51 (the 50 states plus DC) at the midpoint, $21,600 for 300 sq ft. Rank 1 is the costliest.
+What do basic and premium composite deck work cost in Illinois?
For 300 sq ft, basic work runs $14,400 to $20,200 and premium work $23,100 to $28,900. Basic means: entry-level composite boards, low deck, simple shape. Premium means: premium capped or PVC boards, multi-level, hidden fasteners.
+Does the season matter for composite deck in Illinois?
Yes where winters or summers are hard. Of the Illinois metros we cover, Chicago has the most comfortable months (9 of 12) based on NOAA 1991-2020 normals. Our prices do not change by month, so ask contractors whether they charge more or less in busy and slow seasons.
+What does "add a deck railing" add in Illinois?
$2,100 to $6,300 for 300 sq ft, from a national range scaled by the statewide wage and goods indexes.
Composite deck by city in Illinois
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