What a new roof costs in the corridor

The headline numbers

"Typical" assumes a single-family corridor home with a 4/12-7/12 pitch, accessible from the ground or short ladder, and decking in serviceable condition. Steep-pitch (10/12+), multi-story, complex hip-and-valley, walkout-basement roofs, or homes with substantial fascia/soffit work add to all the numbers above.

What's actually in the bid

Tear-off vs overlay

Iowa code (residential) allows up to two layers of asphalt shingles. Overlay is cheaper short-term but worse in almost every long-term respect:

• Hides damaged decking — you can't inspect what you can't see.
• Traps heat, shortening shingle life by ~30%.
• Voids most manufacturer warranties on Class 4 and premium shingles.
• Adds weight (a second layer is ~2.5 lb/sf — meaningful on older homes).
• Hides flashing that should be replaced, not reused.

Tear-off costs typically $1,500-$3,500 more than overlay on a 2,000 sf roof. It's almost always worth it.

Decking

Most corridor homes built since 1990 have OSB or plywood decking that's still serviceable. Older homes — especially 1960s-1980s — may have spaced-board decking or rotted plywood. Decent bids include a decking allowance with per-sheet pricing for replacement:

• OSB sheet, installed: $60-$80
• Plywood sheet, installed: $75-$95
• Actual sheet count determined during tear-off; you're billed for what's used

Underlayment

• Synthetic underlayment over the whole roof. Standard on quality bids. Avoid 15-lb felt — outdated and inferior.
• Ice and water shield at all eaves (Iowa code requires extending at least 24" inside the warm wall line — typically translates to 3-6 ft of coverage along the eave), at valleys, around penetrations (pipes, vents, chimneys), and along rakes if the home has a history of ice damming.

Flashing

Step flashing, kick-out flashing, chimney flashing, and any pipe boots should be replaced — not reused — during a tear-off. Reusing flashing is the most common shortcut on cheap bids. It's also the most common source of post-replacement leaks.

Ventilation

Adequate intake (soffit vents) + exhaust (ridge vent or roof vents) extends shingle life by 30-40% and reduces ice-dam risk in winter. Many older corridor homes have inadequate ventilation; the roof replacement is the right moment to fix it. Adding a continuous ridge vent typically adds $400-$800 to the bid.

Drip edge, rake edge, gutter apron

Metal edging at eaves and rakes. Iowa code requires it. Skip-the-edge bids are cutting code corners.

Insurance pricing vs cash pricing

If your roof replacement is covered by a hail-damage insurance claim, the dollar mechanics are different from a cash replacement.

Cash bids

Roofer measures your roof, calculates squares (1 square = 100 sf), applies their material and labor pricing, includes overhead and profit margin, presents a single total. You compare bids and pick. You pay the contractor directly; financing through a HELOC or contractor finance is common.

Insurance-paid replacements

The carrier sends an adjuster who scopes the loss using a regional pricing database — Xactimate dominates in the Midwest. The Xactimate scope produces line-item pricing for:

• Tear-off (labor + dumpster)
• New shingles (squares + accessories)
• Underlayment, ice and water shield
• Flashing, drip edge, ridge cap, vents
• Decking allowance
• Overhead and profit (typically 10% + 10% on complex claims)

Total Xactimate pricing often lands within 5-15% of typical cash bids in the corridor — sometimes higher, sometimes lower. The contractor bills against the Xactimate scope; supplements (additional line items the adjuster missed) are common and require contractor-to-adjuster negotiation.

How the money flows

1. First check (actual cash value): Replacement cost minus depreciation. Released soon after adjuster approval.
2. Final check (recoverable depreciation): Released after you submit final invoices proving the work was completed. Required to make you whole on a replacement-cost policy.
3. Deductible: Your responsibility. Iowa policies in 2026 commonly have separate wind/hail deductibles of 1-2% of dwelling coverage — often $3K-$8K.
4. Supplements: For additional damage or scope items discovered during tear-off (rotted decking, code-upgrade requirements). Roofer documents, submits to adjuster, gets approval, supplemental payment issued.

See our hail insurance claim page for the full step-by-step.

What pushes a bid higher

• Steep pitch (8/12 and up): more time, safety equipment, slower work. Add 15-30%.
• Two-story or walkout: ground access matters; harder access adds labor.
• Complex roof line: lots of hips, valleys, dormers, skylights. More flashing, more cuts, more waste.
• Skylights, solar tubes, chimneys: each requires separate flashing detail.
• Bad decking: discovered at tear-off, billed against allowance.
• Higher-end shingle: designer or impact-rated lines.
• Code upgrades: bringing an older home up to current code (e.g., adding ice/water shield where there was none).

Class 4 impact-resistant: worth it in Iowa?

Class 4 impact-resistant shingles (UL 2218 rated) cost $3K-$6K more than standard architectural asphalt. Many Iowa carriers offer 10-30% wind/hail premium discounts for Class 4 — sometimes enough to recover the cost differential in 5-7 years. They also hold up better to the routine hail events that batter Iowa roofs.

For most corridor homeowners replacing a hail-damaged roof, Class 4 is the better value choice if you plan to stay 7+ years. See shingles vs metal for the deeper material comparison.

Related

See the corridor roofer directory, how hail damage is scored, the hail insurance claim process, when to get a roof inspection, the asphalt vs metal comparison, and our homeowners insurance overview. For unresolved insurance disputes, see coralvillelaw.com.

Frequently asked