Deck Cost Estimator in Illinois

Compare localized material and professional contractor labor rates for your deck cost project in Illinois (2026 pricing).

Your Deck Details

Decking Material

Deck Size (Area)

100 sq ft 300 sq ft 1,000 sq ft

Deck Elevation

US State

Railing Length

0 ft 40 ft 150 ft

Number of Stair Steps

Built-in Seating

None 0 ft 50 ft

Number of Lights / Fixtures

None 0 fixtures 30

Include Pergola / Cover Include old deck removal

Material Price Comparison

Based on your deck dimensions. Click calculate to see comparison.

How Much Does It Cost to Build a Deck in 2026?

Building a new outdoor deck typically costs between $4,500 and $22,000+. The average homeowner pays around $9,000 to $15,000 for a standard 300-square-foot deck built with wood or composite material, including professional installation.

Average Deck Building Cost by Material (Per Square Foot, Installed)

Material	Material & Labor Cost (Per Sq Ft)	Typical Lifespan
Pressure-Treated Wood	$15 - $35	10 - 15 years
Cedar	$25 - $50	15 - 20 years
Redwood	$30 - $65	20 - 25 years
Composite (Trex, etc.)	$30 - $70	25 - 30 years
PVC Decking	$35 - $75	30+ years
Ipe (Brazilian Hardwood)	$45 - $90	40+ years

Major Cost Factors in Deck Construction

Decking Material: The surface boards account for 40% to 60% of the overall material bill. Pressure-treated wood is the cheapest option but needs annual maintenance. Premium composites or hardwoods cost 2 to 3 times more upfront but last much longer with minimal upkeep.

Size and Shape: Decks are measured by square footage. Rectangular, single-level structures are the cheapest to build. Adding custom shapes, multiple levels, octagons, or complex patterns increases framing labor by 30% to 50%.

Elevation and Footings: A ground-level platform is simple to frame. High decks (second story) require heavy-duty columns, bracing, joists, and safety stairs, adding 15% to 60% to framing labor.

Railings and Stairs: Railings are required for any deck over 30 inches off the ground. Materials vary from simple wood balusters to sleek aluminum, cable, or glass panels, costing $20 to $80+ per linear foot.

How We Calculate Your Estimate

Our deck cost calculator applies real-time contractor surveys and building material rates adjusted for 2026. The calculations start with the selected decking material per-square-foot cost and apply the elevation multipliers. Labor costs are calculated as roughly 50% of the material costs. We then compute optional add-ons like railings, stair steps, built-in benches, LED stair lighting, and old deck removal to provide a comprehensive low-to-high estimate range.

Frequently Asked Questions

Is composite decking worth the extra cost? +

For most homeowners, yes. While composite decking (like Trex or TimberTech) costs 60% to 100% more upfront than pressure-treated wood, it requires zero staining, painting, or sealing. Wood decks must be sealed every 1-2 years, costing $500 to $1,500 each time in materials and labor. Composite pays for itself in maintenance savings within 5 to 7 years.

Do I need a building permit to build a deck? +

Yes, in almost all US municipalities, you need a building permit to build a deck if it is attached to the house, larger than 200 square feet, or higher than 30 inches above the ground. Building permits cost between $100 and $500. Check with your local building office or HOA guidelines before buying materials.

How long does it take to build a standard deck? +

A professional 2 to 3 person crew can usually construct a standard 300-square-foot rectangular deck in 3 to 5 days, depending on weather and footing depth. DIY installations typically take 2 to 4 weekends. Excavation, concrete pouring, and curing for structural footings take the first 48 hours.

What is the average ROI of building a deck? +

According to the Remodeling Cost vs. Value Report, building a wood deck typically recovers 60% to 70% of its initial cost at resale. Composite decks recover roughly 55% to 65%. In addition to financial return, decks significantly boost curb appeal and quicken home sales.