Roof replacement cost calculator
Estimate the cost to replace your roof
Enter the living area from your listing or tax record. Get an itemised budget without an address or sales call.
1 · Start with what you know
Your home
Use living area — the calculator derives the roof surface.
Try a home like yours
Your estimate
Roof replacement budget
Most likely
—Enter your living area to see a range
How the roof size is formed
Home → roof surface- Footprint
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- Coverage inputs
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- Roof surface
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Architectural asphalt shingle
Illustrative cross-section · calculated dimensions, not a roof survey
One number is all it takes. The drawing and budget update together, and nothing is sent anywhere.
- Roof surface
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- Roofing squares
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- Likely / square
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Where the likely cost goes
Built from the same line items as the tableStress-test hidden decking See how a larger tear-off discovery would move this budget
Deck damage is usually confirmed only after tear-off. These are planning scenarios, not predictions.
Enter your living area to begin.
2 · Refine what changes the price
Your roof
Every choice updates the drawing and budget.
Labour rates drive most of the regional difference.
Advanced Roofed extras, known roof size, decking, skylights, permits
Attached garage, covered porch, carport, or breezeway not included in living area. Enter horizontal footprint—not sloped roof surface or another living floor.
The measured roof area below controls this estimate, so this footprint is not added again.
If a roofer measured it, enter it here and the tool stops estimating the size.
Repair it or replace it? Use condition and time horizon before assuming a full reroof
Best estimate is enough.
This affects economics, never the safety call.
Enter the roof age and how long you expect to stay. The replacement estimate above remains visible for comparison, not as a recommendation.
This is a triage prompt, not an inspection. Do not climb onto a damaged roof.
Private roof bid audit Compare totals, contractor-stated squares, unit-price exposure, and written scope
All three stay in this browser. Compare identical scope, not price alone.
Audit each written quote
Keep total entry fast. Add only the contractor-stated facts you can verify in writing.
Written bid and quantity facts
Record only what the proposal states; none of these fields changes the site estimate.
Contractor A facts
Optional. These facts audit the bid; they never change the primary estimate.
Quantity basis
Keep measured roof surface separate from shingles ordered after trim and waste.
Use the contractor-measured roof plane, before material-order waste.
Copy the material quantity from the proposal or order record.
Packaging varies. Check the wrapper, product sheet, or written order.
- Site model
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- Measured surface
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- Material ordered
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- Order bundles
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- Order delta
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- Order difference %
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Enter measured surface or a material order. These facts audit the quote and never change the estimate.
Price per replacement 4×8 sheet.
Written contractor workmanship term, not the manufacturer warranty.
Manual note only. The text helper does not interpret product quality.
Find basic facts in pasted text Total, roofing squares, shingle bundles, and decking price Not sent or saved
Paste text, then choose Find basic facts locally. Nothing runs while you type.
Scope and written signing checks
Separate what is written from what still needs clarification before signing.
0 of 8 marked as listed · 8 to clarify
Before signing · Contractor A 0 of 8 confirmed in writing · 8 to review Manual review
Mark only what you have confirmed in the written contract. Unchecked means “review before signing,” not a legal violation.
General consumer-preparation checklist only. Contract and payment requirements vary by state and locality.
Contract and project arithmetic
Reconcile the written schedule, approved changes, payments, and final invoice without a legal verdict.
Project cost control · Contractor A No payment schedule or written changes entered This tab only
Reconcile the written payment schedule, approved changes, recorded payments, and final closeout documents. The tool reports arithmetic only; it does not decide whether a schedule or document is legally sufficient.
Payment schedule
Enter the dollar amounts written for each milestone. Mark a row paid only after you record that payment.
Written change orders
Only rows marked approved in writing change the revised contract total. Pending rows stay separate.
- Original quote
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- Approved changes
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- Revised contract
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- Scheduled
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- Recorded paid
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- Remaining
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Final invoice reconciliation
Compare the invoice total and shown balance with the revised contract and payments recorded above.
Total printed on the final invoice, before subtracting prior payments.
The remaining balance printed on that invoice.
- Revised contract
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- Final invoice
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- Invoice difference
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- Recorded paid
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- Expected remaining
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- Invoice balance
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- Balance difference
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- Invoice-implied prior payments
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Final-payment closeout
Mark only what is documented, received, or completed. Unchecked means review before final payment.
Memory-only worksheet. Invoice, payment, lien, inspection, warranty, and closeout requirements vary by jurisdiction and contract.
Closeout and roof record
Retain the final documented roof system and warranty facts for future service or ownership handoff.
As-built roof & warranty record · Contractor A No handoff facts recorded This tab only
Record exactly what was installed and what the written warranty documents say. This does not register or validate a warranty.
Record the installed or final documented quantity, not an inferred bundle count.
Plain record only. The tool does not contact or verify a manufacturer.
Record the facts you want retained in the project pack.
| Quote | Price | Vs. likely | Per square | Read | Scope |
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Enter at least one quote for an individual read; add a second for comparison.
P19 · compare recorded facts
Cross-quote differences to reconcile
Add a second written quote to compare recorded differences.
A difference means only that the values or marked written scope are not the same. It is not proof of an error, omission, fault, overcharge, or better contractor.
Appendix · A–C comparison
Detailed model and contractor matrix
| Audit fact | Model | A | B | C |
|---|
Measured roof surface and material ordered are separate facts. Bundle packaging varies by product, and every order difference shown here is arithmetic—not a judgment about normal waste, over-ordering, shortage, or refund entitlement.
Take the model into the conversation
Roof project review pack
Built locally from this roof, measured and ordered quantities, quote facts, project arithmetic, closeout review, and the as-built handoff record.
Enter a home size to generate roof-specific questions and a printable project review pack.
Insurance out-of-pocket: ACV vs RCV See how depreciation and the deductible change what you fund
Used only for the depreciation illustration.
Check for a separate wind, hail, or roof deductible.
| Planning figure | RCV policy | ACV policy |
|---|---|---|
| Estimated replacement cost | — | — |
| Estimated depreciation | — | — |
| Possible first check | — | — |
| Possible later payment after work | — | — |
| Estimated amount left to you | — | — |
Enter a roof age and deductible after you have an estimate.
Planning illustration only — not a coverage decision or settlement offer. Carriers can use a different depreciation schedule, condition adjustment, roof endorsement, policy limit, or payment timing.
Where the money goes Every line item, with its source
| Line item | Low | Most likely | High |
|---|---|---|---|
| Total | — | — | — |
Your breakdown appears once you enter a home size.
Compare materials on your roof Total cost and cost per year of life
| Material | Most likely | Life | Per year |
|---|
Cost per year divides the estimate by the midpoint of the material’s expected life. It ignores maintenance, repairs, and the fact that you may move before the roof wears out.
Enter a home size to compare materials.
What would move this number The factors worth pinning down before you sign
Enter a home size to see what matters most.
Method, sources, and limits How the number is built and what it cannot know
Working out your roof
living footprint = living area ÷ stories
total footprint = living footprint + additional roofed footprint
roof area = total footprint × pitch factor × area factor
The pitch factor is arithmetic, not opinion: √(rise² + 144) ÷ 12. A 6/12 roof is 1.118×
larger than its footprint; a 12/12 roof is 1.414× larger. The area factor (1.07–1.18) covers the eave
overhang and the extra planes a cut-up roof carries — real surface a roofer measures, not offcuts. The
material you buy and throw away when cutting is already inside the published per-square prices, so it is
not counted twice. An attached garage, covered porch, carport, or breezeway can be added as horizontal
roofed footprint when it is not part of living area. That extra is added after the story divisor. A
measured roof-area override replaces this derived path and is never increased by the extra again.
This is the single biggest reason published numbers disagree. A “2,000 sq ft roof” and a “2,000 sq ft house” are not the same thing. A 2,000 sq ft single-story home has roughly 2,400 sq ft of roof. The same home over two floors has roughly 1,200.
Building the cost
Every line item is priced as a low–high band from published 2026 cost data. “Most likely” is the midpoint of that band — a convenience, not a separate measurement. Labour premiums for steep pitch and multi-story access apply to the labour share only, taken as 55% of installed cost.
Why published averages disagree by more than double
Cost guides report a US average near $12,000 for an asphalt replacement. The Remodeling Cost vs. Value report puts the same job at $31,871 — because it prices a specified 30-square hip roof with two skylights, synthetic underlayment, drip edge, and aluminium flashing. Neither is wrong. They describe different jobs. That is why this tool gives you a range and shows you the line items rather than a single confident number.
Regional adjustment
States with a directly published cost figure are marked measured. Every other state is assigned to the nearest cost tier from published construction-wage patterns and is marked grouped. The interface tells you which one you are getting. A grouped state is a regional adjustment, not local pricing.
Decision aids after the estimate
Repair-versus-replacement is a conservative triage, not a diagnosis. Widespread damage around 30% or more weighs toward pricing replacement; local damage, few leaks, material life, and how long you expect to stay determine whether repair is a reasonable first scope or an inspection is the honest answer.
The insurance comparison uses the displayed most-likely cost as a planning RCV and straight-line useful-life depreciation to illustrate ACV, a possible first payment, and recoverable depreciation. Your policy, carrier, state law, roof endorsement, condition, limits, and deductible control the real claim.
Measured roof surface, material order, and bundles
A roofing square is 100 sq ft of roof surface. The contractor-measured roof surface and the material order are separate quantities: the order can be larger because it may include cutting, starter/ridge products handled elsewhere, breakage, or retained material. This tool reports only the signed arithmetic difference; it does not decide whether an order allowance is normal, excessive, deficient, or refundable.
Bundle packaging is product-specific. Many common shingles use three bundles per square, while other products use four, six, or another value. The default of three is only a typing convenience. Check the wrapper, product data sheet, or written order before converting bundles. See Owens Corning’s roofing quantity guidance and the exact manufacturer product specification for the shingle being installed.
Before signing
The manual pre-sign checklist is based on general consumer guidance to review contractor credentials, proof of insurance, written materials and scope, project dates, permits, payment milestones, change orders, cancellation notices, and blank spaces. Exact contract and payment rules vary by jurisdiction. A checked item means only that you marked it confirmed in writing; it is not a legal-compliance result or a recommendation to sign.
General guidance is available from the Federal Trade Commission, your state or local contractor-licensing authority, and consumer-protection offices.
Payments, final invoice, and roof handoff
The payment worksheet copies five written milestone amounts and checks whether they add up to the original quote plus change orders you marked approved in writing. It can also total amounts you mark recorded paid and show the remaining arithmetic. It does not recommend a deposit, label a schedule front-loaded, or decide when payment is legally due.
Final-invoice reconciliation compares the invoice total with the revised contract total, compares the invoice balance with the remaining amount from payments you recorded, and checks the prior-payment amount implied by those two invoice figures. It runs only after you confirm that all approved written additions and credits have been entered. A difference means only that the documents and entries need reconciliation; it is not an overcharge, debt, or instruction to pay or withhold money.
The as-built handoff record stores only the installation date, exact product/system details, installed quantity, accessories, warranty wording, and registration reference you type. Manufacturer rules differ: for example, GAF separates base and enhanced registration paths, while Owens Corning asks for installation date, shingle type, color, and installed squares when registering. This page never registers, transfers, or validates a warranty. Use the official GAF registration resources or Owens Corning warranty resources for the product actually installed.
Change additions and credits affect the revised contract total only after you mark them approved in writing. Pending rows remain separate. The closeout checklist records what you marked documented or completed; it does not determine inspection status, lien status, warranty validity, or whether final payment is legally safe.
The FTC recommends written estimates and contracts, warns against paying the full project amount up front, and says final payment should wait until work is complete and satisfactory. Exact contract, payment, change-order, lien-release, and closeout rules vary by jurisdiction. See the FTC homeowner guidance, Massachusetts consumer guidance, and jurisdiction-specific authorities such as the California CSLB lien-release guidance.
What this tool cannot know
- The condition of your decking. It is only visible once the old roof is off.
- Your local permit office’s fee schedule.
- Storm-driven price surges, which can move a whole metro for a season.
- Your contractor’s overhead, warranty, crew, and how busy they are this month.
- Anything about your actual roof. Nobody has measured it.
This is a budgeting estimate, not a quote. Use it to size up the job and to ask better questions. Only a roofer on your roof can price it.