Composite Deck Cost in Illinois
A Composite deck in Illinois costs $35-$95/sqft installed with the state's 1.00× labor multiplier (Midwest). Generic composite covers the entire wood-plastic-composite + capped composite + PVC market — Trex, TimberTech, Fiberon, Deckorators, MoistureShield, Wolf, Zuri, NewTechWood, DuraLife. Average 25-yr lifespan + no maintenance is the value vs PT pine which needs annual staining. Illinois labor 1.00× national (Midwest baseline). Chicago's permit process is more involved than downstate.
Composite cost by deck size in Illinois
Mid-tier Composite (TimberTech Pro Legacy) at Illinois's 1.00× labor multiplier — ~$58/sqft installed.
Cost ranges include materials + labor + standard railing. Excludes permit ($175 baseline + 1.2% of project value), demolition (if replacing), and footings for 42″ frost depth.
Composite product lines in Illinois
Composite installed cost ranges from $35/sqft (entry tier like Trex Enhance Basics) to $95/sqft (luxury PVC like AZEK Harvest). National median is $50-58/sqft for a mid-tier 2026-Q1 build — multiply by your state labor multiplier for local pricing.
Illinois-specific notes
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FAQ — Composite in Illinois
How much does a Composite deck cost in Illinois?▾
In Illinois, Composite decking costs $35-$95/sqft installed (national $35-$95/sqft × Illinois's 1.00× labor multiplier). A typical 16×20 (320 sqft) Composite deck lands around $20,800. Mid-tier TimberTech Pro Legacy runs about $18,560 for the same scope.
Which Composite line is best for Illinois's climate?▾
Illinois's freeze-thaw cycles favor PVC over composite where budget allows. Fiberon Sanctuary works well in snow regions when properly fastened with the right expansion gap.
What's the permit fee for a Composite deck in Illinois?▾
Illinois permit fees typically run $131-$324 depending on jurisdiction and project value — most calculators use max(regional baseline $175, 1.2% of project value). Chicago metro permits $250-400. Frost depth 42″ across most of state.
How deep do footings need to be for a Composite deck in Illinois?▾
Illinois's frost depth is approximately 42″. Composite doesn't change the footing requirement — that's IRC R403.1.4-driven by frost line. Use Sonotube 10-12″ depending on tributary area. Verify with your local building department since AHJs sometimes require deeper depths than the state-published value.
Is Composite worth the money in Illinois?▾
Composite vs PT pine over 25 years in Illinois: PT pine = ~$30/sqft installed + ~$3/sqft/yr maintenance (stain/seal annually) = $93/sqft total. Composite mid-tier = $58/sqft installed + $0 maintenance = $58/sqft total. Composite typically wins the 25-yr TCO comparison by 20-40%, plus better resale value.
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