Illinois Construction Estimating Services

Illinois is one of the most cost-layered construction markets in the country. Cook County union wages run 30 to 40 percent above the national average. Chicago’s permit fee schedule adds a cost layer most out-of-state estimators miss entirely. The Illinois Prevailing Wage Act applies to every public works project — county by county, trade by trade, updated every June. And RSMeans cost indexes vary by more than 30 points between Chicago’s Loop and Carbondale in the south.

If your estimate doesn’t reflect those layers, your bid is wrong before it leaves the desk.

Our company delivers Illinois construction estimates built on:

• Current Illinois Department of Labor prevailing wage schedules
• RSMeans city-specific cost data
• Local permit fee structures across the Chicago metro
• The collar counties
• Downstate markets

No other Midwestern state has a wider internal cost spread than Illinois. A carpenter in Cook County earns roughly $62 per hour in base wages before fringes. The same trade in Williamson County downstate earns around $38. That $24-per-hour gap — multiplied across a 15,000-hour project — is a $360,000 swing in the labor line alone.

Three variables drive this gap:

Residential construction costs depend on the location and project type. Expensive condos in Chicago’s Streeterville neighborhood are located at the high end. Single-family custom homes in Lake County offer mid-to-high cost estimates. Affordable housing projects downstate come in at much lower price points.

Chicago high-rise residential (10+ stories, concrete or steel frame): Shell costs typically run $350 to $550 per SF. Finish-out adds $80 to $220 per SF depending on unit specification. High-rise in Chicago also triggers the Chicago DOB’s Structural Peer Review requirement on projects over 75 feet, adding $15,000 to $45,000 in peer review fees.

Suburban single-family and multifamily (collar counties — DuPage, Lake, Will, Kane, McHenry): Hard costs typically run $180 to $280 per SF for new single-family construction, applying the collar county CCI of 112 to 115. Custom homes in high-end Lake County submarkets exceed $320 per SF without site work.

Downstate residential (Peoria, Springfield, Champaign, Rockford): New residential costs run $120 to $175 per SF applying the relevant city CCI in the 95 to 103 range. Material costs are comparable to Chicago; labor is significantly lower.

Illinois-specific residential factors SMA builds into every estimate:

• Energy code: Illinois uses updated rules for energy saving. Sealing air leaks and installing heating or cooling systems add to the overall cost based on local weather.
• Radon mitigation: Every new house built must have a system to block dangerous radon gas. Installing these basic underground pipes costs between $800 and $1,400 per home.
• Illinois Radon Awareness Act disclosure: Affects renovation scopes for resale properties.

Commercial construction in Illinois — office, retail, hospitality, healthcare, and mixed-use — is driven primarily by the Chicago metro, which accounts for the majority of the state’s commercial construction volume by dollar value.

Illinois commercial construction hard cost ranges (2026):

Commercial-specific Illinois compliance cost factors:

• Chicago permit fees on commercial buildouts 
• Special inspections (IBC Chapter 17) 
• Chicago Green Permit Program

Illinois is one of the most active industrial construction markets in the Midwest.  The I-55 and I-80 corridors in Will, Grundy, and Kendall Counties have seen sustained speculative warehouse and distribution construction since 2021.

Illinois industrial construction hard cost ranges (2026):

The Illinois Department of Labor publishes prevailing wage rates by county every June under 820 ILCS 130. Below are representative straight-time base wage rates for common trades across three Illinois market tiers. Fringe benefits add $20 to $35 per hour on top of the base rate and are not included below.

Source: Illinois Department of Labor Prevailing Wage Schedules, effective June 2026. Straight-time base wages only. Fringe benefits, overtime, and weekend premiums not included. Verify current rates at labor.illinois.gov before bidding.

SMA applies the correct county-level rate to every trade line in every Illinois estimate — not a blended statewide average. On a 15,000-hour commercial project, applying Cook County rates to a Springfield project overstates labor by $180,000 to $280,000. The opposite error on a Chicago bid underbids by the same amount.

RSMeans City Cost Indexes (CCI) measure how local construction costs compare to the national baseline of 100.0. Illinois has one of the widest internal spreads of any state — apply the wrong city index and you misestimate total project cost by 20 to 30 percent. SMA applies labor and material sub-indexes separately by trade division, not a single composite multiplier applied to total cost.

Every Illinois public works project has to follow the Illinois Prevailing Wage Act (820 ILCS 130/). The most important things that your estimate must have are:

• Job Site Posting: You must display current wage rates at the worksite.
• Payroll Records: Save certified payroll records for three years in case the Illinois DOL asks to see them.
• Subcontractor Rules: Main contractors are fully responsible for making sure all subcontractors follow wage rules.
• Fringe Benefits: Pay health, pension, and vacation benefits into an approved plan, or add that money directly to the worker’s hourly pay.
• June Rate Changes: Wage rates update every June, so projects running past May could see cost increases. SMA marks this risk on all Illinois estimates.

For Illinois projects with federal funding — IDOT highway work, HUD-assisted housing, EPA water infrastructure, FEMA-funded projects — Davis-Bacon Act requirements apply alongside state prevailing wage. Where the two schedules conflict, the higher rate governs. SMA reconciles both schedules for every trade on federal-aid Illinois estimates — a step most estimators skip.

A permit cost for a $5M commercial project in the City of Chicago is between $45,000 and $90,000.

Permit fees in Illinois municipalities outside Chicago are less standardized. DuPage County municipalities typically run 0.5 to 1.0 percent of construction value. Collar County suburbs range from flat-rate fees under $2,000 for small projects to percentage-based schedules on larger commercial work. Downstate municipalities often charge flat-rate or low-percentage fees significantly below Chicago levels. SMA obtains and applies the current fee schedule for the specific project municipality on every Illinois estimate.

Illinois does not issue a statewide general contractor license. Licensing is handled at the local level — requirements for a Chicago project are entirely different from a Peoria project.

• General Contractor: Needs a City of Chicago license for any work over $500.
• Electrical: Requires a Chicago license, with work done by licensed electricians.
• Plumbing: Needs both an Illinois state license and a Chicago city license.
• HVAC: Requires EPA certification for refrigerant and a Chicago HVAC license.
• Demolition: Needs a Chicago demolition license, plus an asbestos check for buildings built before 1980.

These apply regardless of municipality:

• Roofing: Illinois Roofing Industry Licensing Act — state license required for any roofing contractor
• Plumbing: IDFPR license required statewide for all plumbing work
• Asbestos abatement: Illinois EPA NESHAP certification required
• Lead abatement: IDPH certification required on residential properties built before 1978

Unlicensed subcontractor bids are non-compliant on Illinois public works projects and create liability exposure on private projects. SMA flags potential licensing compliance gaps during the estimating process when scope elements trigger these requirements.

Project type: 22,000 SF tenant improvement, Class A office, 22nd floor. Location: Chicago, IL (Cook County). Client: General contractor bidding a negotiated GMP for a financial services firm

The challenge: The GC needed a GMP-quality cost estimate in 72 hours to support a lease negotiation deadline. The project involved full MEP fit-out with a raised access floor system, a distributed antenna system, and a 400A electrical service upgrade — all on an occupied floor requiring weekend-only shutdown access for demolition.

What SMA delivered:

• Full CSI Division 03–16 estimate applying Cook County prevailing wage rates to every trade line
• Separate cost analysis for the service upgrade, coordinated against ComEd point-of-delivery requirements
• Weekend-premium labor uplift (30% per the Cook County carpenters’ agreement) applied to the demolition scope
• Three system alternates: standard raised floor vs. low-profile system vs. carpet with underfloor access hatches — with cost differentials for each

Result: $2.74M GMP established. Actual final cost: $2.81M — a 2.6 percent variance against our estimate. The weekend demolition premium was the single most material line item the owner had not anticipated. SMA surfaced it in the estimate, and the GC negotiated a phased access schedule that eliminated $38,000 of the premium before GMP signing.