"How much is a new roof?" is the first question most homeowners ask. The honest answer is that it depends on the roof. Two houses on the same street can have very different prices. Instead of quoting a number that might not fit your home, this guide explains the factors that set the price of a residential asphalt shingle roof replacement in Illinois, and what a complete estimate should include.
What Affects the Cost of a Shingle Roof
Roof size (squares)
Roofers measure in "squares" (100 square feet of roof surface). A bigger roof needs more shingles, underlayment, and labor. Roof area is usually much larger than the home's floor area, especially with steep slopes or overhangs.
Pitch and height
Steep roofs and two-story homes take more safety setup and time. Walkable, low-slope roofs generally cost less per square than steep ones.
Number of layers to tear off
Removing two or more old layers takes more labor and disposal than a single layer. We recommend full tear-off so we can inspect the decking.
Decking condition
Soft, rotted, or delaminated decking (sheathing) must be replaced before new shingles go on. You won't know exactly how much until the old roof is off, so a good estimate explains how decking repairs are priced.
Ventilation
Balanced intake and exhaust ventilation helps a shingle roof last. Adding or correcting ridge vents, box vents, or soffit intake can change the price.
Flashing, chimneys, skylights, and valleys
Every penetration and wall needs proper flashing. Chimneys, skylights, dormers, and multiple valleys add detail work.
Underlayment and ice-and-water protection
Synthetic underlayment and ice-and-water barrier at eaves and valleys protect against wind-driven rain and ice dams.
Shingle choice
Architectural (dimensional) asphalt shingles from manufacturers like CertainTeed come in different product lines. Premium lines and accessories (starter, hip and ridge) cost more and may come with different manufacturer warranty options.
Permits and local rules
Permit requirements and fees vary by town. For example, Greenville lists a roof permit on its fee schedule and Edwardsville requires a roof permit, while Columbia and the City of Effingham say re-roofing generally doesn't need a city permit. Your estimate should say who handles the permit.
Access, disposal, and cleanup
Driveway access, landscaping protection, dumpster placement, and debris haul-off all play a part, as does a magnetic nail sweep at the end.
Insurance vs. out-of-pocket
If storm damage is covered, your insurer's estimate sets what it pays and you pay your deductible. For an age-related replacement, you pay the contract price directly.
Want a real number for your roof?
Call or text MPR Roofing for a free, no-pressure inspection.
What a Good Estimate Should Include
- Roof size in squares, and the number of layers being removed
- Shingle manufacturer and product line, plus starter and ridge cap
- Underlayment type and ice-and-water barrier locations
- Flashing, drip edge, pipe boots, and ventilation work
- How decking replacement is priced if bad boards are found
- Permit handling, cleanup, and disposal
- The contractor's Illinois roofing license name and number (required on Illinois roofing contracts and bids)
Illinois law also requires a written contract for home repair jobs over $1,000, and contractors must give you the "Home Repair: Know Your Consumer Rights" pamphlet. See our roof insurance claim guide for storm-related replacements.
Related: Roof replacement • CertainTeed shingles • Free roof inspection
Last updated 2026-10-18. Written by MPR Roofing (Meyer Professional Roofing), Illinois Roofing License #104.020135. This guide is general information, not legal or insurance advice. Check your policy and current law for your situation.