Illinois Roofing License IDFPR #19HC00108700 · GAF Certified Contractor
The base price for a Trill Roofing replacement in the Riverbend is $4.50 to $7.50 per square foot installed for architectural asphalt shingles. From there, six variables move your specific quote up or down. This guide explains each variable, gives realistic ranges, and lets you build a rough estimate for your home before any contractor walks the roof.
Variable 1: Roof square footage
Total roof surface area, not floor area. Roof square footage is typically 1.3-1.7x the home’s floor area depending on pitch and overhangs.
For a typical 2,000 sq ft floor-area home:
- Low-pitch (4/12): ~2,400-2,800 sq ft of roof
- Standard pitch (6/12): ~2,800-3,200 sq ft of roof
- Steep pitch (9/12+): ~3,200-3,800 sq ft of roof
Cost at $5.50 per sq ft midpoint:
- 2,500 sq ft roof: ~$13,750
- 3,000 sq ft roof: ~$16,500
- 3,500 sq ft roof: ~$19,250
Variable 2: Pitch
Steeper roofs cost more to install (labor + safety):
- 2/12-5/12 (low to moderate): base pricing
- 6/12-8/12 (standard): base pricing, no premium
- 9/12-10/12 (steep): ~15-25% labor premium
- 11/12-12/12+ (very steep): ~30-50% labor premium
Pitch premium reflects the slower work, roof jacks, and safety harnessing required.
Variable 3: Complexity (valleys, dormers, chimneys)
A simple gable roof is cheapest. Each complexity element adds labor:
- Each valley: +$300-$500 for labor and flashing
- Each dormer: +$400-$800 for cut shingles and flashing
- Each chimney: +$600-$1,400 for re-flashing (more if cricket needed for wide chimneys)
- Each skylight: +$200-$400 for flashing integration
- Other penetrations (pipes, vents): minor add per item
A roof with 4 valleys + 2 dormers + 1 chimney + 1 skylight = $2,500-$4,500 in complexity premium over a simple gable of the same square footage.
Variable 4: Decking condition
Decking replacement is at-cost (no markup at Trill Roofing). Typical sheet replacement:
- $60-$90 per sheet of 1/2″ OSB or plywood installed
- 5 sheets needed: $300-$450 added
- 15 sheets needed: $900-$1,350 added
The number can only be finalized after tear-off. For most homes built after 1990 with adequate ventilation, expect 0-5 sheets. Older homes (pre-1980) or homes with chronic moisture issues can have 10+ sheets.
Variable 5: Shingle tier
Your shingle line choice changes the materials cost:
| Tier | Price per sq ft installed | Lifespan |
|---|---|---|
| 3-tab (skip these) | $3.50-$4.50 | 15-20 yr |
| Standard architectural | $4.50-$6.00 | 25-30 yr |
| Premium architectural | $5.50-$7.00 | 30-35 yr |
| Class 4 impact-resistant | $6.00-$8.50 | 25-35 yr (+ IL insurance discount) |
| Designer / luxury | $9.00-$13.00 | 40-50 yr |
Variable 6: Tear-off layers
Standard tear-off (single existing layer) is included in base pricing. Two-layer tear-off (when an overlay was done previously) costs more:
- Double dumpster capacity needed
- 2x dump fees
- 2x labor for tear-off
- Adds approximately $1.00-$2.00 per sq ft
Worked example: Riverbend 2-story colonial
Hypothetical: 2,200 sq ft floor area, 2-story Riverbend home, 6/12 roof, simple gable with 2 valleys and 1 chimney, single existing shingle layer, standard architectural shingle install.
- Roof sq ft: ~3,000
- Base: 3,000 × $5.50 = $16,500
- Complexity: 2 valleys ($800) + 1 chimney ($1,000) = +$1,800
- Decking: ~5 sheets estimated = +$400
- Subtotal: $18,700
Variations on the same home:
- Same with Class 4 shingle upgrade: ~$20,200
- Same with designer/luxury shingle: ~$28,500
- Same with two-layer tear-off: ~$23,200
This is illustrative – get a Trill Roofing inspection for an actual quote on your specific home.
Schedule an accurate quote
Free inspection at /free-inspection/ produces a written, itemized estimate within 48 hours that breaks each variable out as a separate line item. No surprises, no hidden cost categories.
Related Trill Roofing Services
Get a free roof inspection from Trill Roofing
No-pressure, written estimate. Family-owned. IL-licensed. Serving Godfrey and the Riverbend.