Roof Replacement Cost Calculator: Check Your Quote Line by Line
A roofing quote arrives as one number. Inside it are eight or nine separate things, and you can check most of them yourself with a tape measure and public data. This page shows the arithmetic, gives you a calculator that produces both a total and a materials list for your roof, checks the quote you were given against a published benchmark for your part of the country, and tells you plainly which parts we cannot verify for you.
What you can check, and what you can't
Most cost guides hand you a range — "$8,000 to $15,000" — and stop. That range cannot tell you whether the quote in your hand is fair, because it doesn't say which line is out of position. Here is the honest breakdown of what is checkable:
| Line item | Can you verify it? | How |
|---|---|---|
| Roof area | Yes | Geometry. Footprint × pitch factor. |
| Material quantities | Yes | Area and perimeter drive every quantity. |
| Code minimums | Yes | Published building code. |
| Tear-off weight | Yes | Shingle weight per square × layers. |
| Labor hours and wages | Mostly | Federal wage data, plus a stated productivity assumption. |
| Material prices | No | US retail prices are not open data and every source we tested blocks automated access. Ask for brand, product line and quantity instead. |
| The total | Yes, against a benchmark | A published, scope-defined national and regional figure, scaled to your roof. |
| Overhead and profit | No | The contractor's business. But it should be disclosed. |
Calculator
Your roof, by the numbers
Measurements
Measure the outside of the walls at ground level. This assumes a simple gable roof; hips, dormers and valleys add area and hours.
Labor
2025 U.S. national mean for roofers. Substitute your state's figure — see sources.
Ventilation
The 1/300 exception applies where a Class I or II vapor retarder is installed in Climate Zones 6-8, or where 40-50% of the vent area sits in the upper portion of the attic. See Step 6.
Where the roof is
Your total
| Your roof | — |
| Benchmark rate, — | — |
| Benchmark total for your roof | — |
| of which field labor, our model | — |
| of which everything else | — |
The benchmark is the 2025 Cost vs. Value Report figure for a 30-square job, divided by 30 and scaled by your Census division. That job is specified as a rectangular hip roof with flashing at two skylights and a custom ridge cap. A plain gable with no skylights is less work, so landing under the benchmark is normal and is not by itself evidence of a good price.
Area
| Plan area including overhang | — |
| Roof surface area | — |
| Roofing squares | — |
| Squares to order (with waste) | — |
Materials your quote should list
| Shingle bundles | — |
| Ice barrier at eaves | — |
| Underlayment (remaining field) | — |
| Drip edge | — |
| Starter strip | — |
| Ridge cap | — |
| Roofing nails | — |
Tear-off and disposal
| Old roofing weight | — |
| Dumpster size | — |
Attic ventilation required
| Attic floor area | — |
| Net free vent area required | — |
| at the ridge (upper) | — |
| at the eaves (intake) | — |
Labor
| Labor-hours | — |
| Crew days | — |
| Direct wages | — |
| + burden | — |
| Labor as billed to you | — |
Where the total comes from
The total above is not the sum of a shopping list. We tried to build it that way and could not, and the reason is worth stating plainly: United States retail material prices are not available as open data. On 31 August 2026 we attempted automated collection from Home Depot, Lowe's, Menards, Build.com, SupplyHouse and Walmart. Every one refused — four with an outright block, two by publishing no price in the page itself. We are not going to invent numbers to fill that hole.
So the total comes from the other direction, and it is the better direction anyway. The quote in your hand is an installed price. A pile of receipts is not the thing you are being asked to compare it against.
The benchmark
Since 1988, Remodeling magazine — now Zonda, published through the Journal of Light Construction — has priced the same defined set of remodeling jobs every year across US markets. The 2025 edition, its 38th, is the source of our number. Its roofing project is specified, not vague. It is:
- tear-off to bare wood sheathing, with disposal
- 30 squares installed
- asphalt shingles of at least 235 lb, carrying at least a 25-year warranty
- 30 lb felt or an equivalent synthetic underlayment
- galvanized drip edge and mill-finish aluminum flashing
- a rectangular hip roof
- custom flashing at two average-size skylights
- a custom cap treatment at a vented ridge
The 2025 national average job cost for that work is $31,871. Thirty squares divides into it at $1,062 per square. That is the figure the calculator scales to your roof.
Two things follow from the scope, and both matter to you:
It is a hip roof with two skylights. Hips take more cutting than gables, and skylight flashing is slow, fussy work. If your roof is a simple gable with nothing penetrating it but a plumbing vent, the benchmark is describing a harder job than yours. Coming in under it is expected. It is not, on its own, evidence that your price is good.
It is a 235 lb shingle with a 25-year warranty. That is an entry-level product. If you are being quoted a heavy architectural shingle with a lifetime limited warranty, your material line is above what this benchmark assumes.
Where you live moves it more than anything you choose
The same report breaks the country into the nine US Census divisions. The spread between the cheapest and the most expensive is 1.43× — the Middle Atlantic runs near $1,240 a square while the East South Central runs near $865, for identical specified work. Nothing about the roof changed. Wages, insurance rates, disposal fees and what the local market will bear did. The calculator applies your division automatically once you pick your state.
The direction of travel
The same national figure was $19,528 in 2015. It is $31,871 in 2025 — up about 63 percent in ten years. The climb was not smooth. It peaked at $31,535 in 2022, fell to $29,136 in 2023, then recovered through $30,680 in 2024 to today’s figure. If you were quoted a roof a few years ago and are comparing that memory against a quote in front of you now, the memory is the thing that is out of date.
The finding that should change how you read your quote
Put the two halves of this page together. The benchmark says a defined 30-square job costs $31,871. Our labor model, built on the federal wage for roofers, says the field labor inside that job is about $3,700.
That is 11.5 percent. Roughly one dollar in nine.
The obvious objection is that our labor assumptions are too soft, so we pushed them hard in the other direction. Every row below uses the same 30 squares and the same benchmark:
| Scenario | Hours/sq | Burden | O&P | Billed labor | Share |
|---|---|---|---|---|---|
| Fast crew, modest markup | 1.5 | 30% | 35% | $2,207 | 6.9% |
| Our defaults | 2.5 | 30% | 35% | $3,679 | 11.5% |
| Slow crew, high comp state, heavy markup | 4.0 | 65% | 60% | $8,855 | 27.8% |
| Implausibly slow and expensive | 5.0 | 80% | 75% | $13,206 | 41.4% |
Push it to a point no roofing company could survive and field wages still do not reach half the price. What you are paying for is mostly not the crew.
This is not an accusation. The remainder is real cost: shingles and membrane and metal, the dumpster, the permit, general liability and workers' compensation insurance at rates roofing carries and few other trades do, the truck, the salesperson who came to your house, the office, the warranty the company is promising to honour in fifteen years, and profit. But it does tell you where to aim your questions. Arguing a contractor down on crew hours is arguing about the ninth dollar. Ask instead what the material line is, what the overhead and profit percentage is, and what the warranty is worth — that is where the other eight dollars live.
Step 1 — Footprint to roof area
Your roof is larger than the ground it covers, because it slopes. The conversion is geometry, not opinion:
pitch factor = √(rise² + 12²) ÷ 12
| Pitch | Factor | 1,344 sq ft plan area becomes |
|---|---|---|
| Flat (0:12) | 1.000 | 1,344 sq ft |
| 4:12 | 1.054 | 1,417 sq ft |
| 6:12 | 1.118 | 1,503 sq ft |
| 8:12 | 1.202 | 1,615 sq ft |
| 10:12 | 1.302 | 1,749 sq ft |
| 12:12 | 1.414 | 1,901 sq ft |
Roofers price in squares. One square is 100 sq ft. A 40 × 30 ft house with 12-inch overhangs has a plan area of 1,344 sq ft; at 6:12 pitch that is 1,503 sq ft of roof, or 15.0 squares. You order about 17 squares to cover cuts, starter courses and valley waste.
Check this first. If a quote states your roof area, compare it. A quote claiming 2,200 sq ft for this house is overstating by nearly half. Ask how it was measured — aerial measurement reports are common and should be shareable.
Step 2 — The takeoff your quote should show
A shingle roof is not one product. It is seven or eight, and every quantity is driven by two numbers you now have: area and perimeter. A quote that lists only "shingles" is hiding most of the job.
| Item | Driven by | What it does |
|---|---|---|
| Shingles | Area + waste | The visible roof. Sold in bundles, usually three to a square. |
| Ice barrier | Eave length × required width | Self-adhering membrane at the eaves. Stops meltwater backing up under shingles. Code-required in cold regions — see Step 3. |
| Underlayment | Remaining roof area | Secondary water barrier over the rest of the deck. |
| Drip edge | Perimeter | Metal flashing at eaves and rakes. Code-required on shingle roofs. |
| Starter strip | Perimeter | First adhesive course. Skipping it is a common shortcut that shows up as blown-off edges. |
| Ridge cap | Ridge + hip length | Caps the peak. Field shingles cut down for cap is a downgrade — ask. |
| Nails | Area | Four per shingle standard, six in high-wind zones. |
| Ventilation | Attic floor area | Ridge vent, soffit intake. Under-ventilated attics shorten shingle life and can void warranties. |
The calculator above produces these quantities for your dimensions. Take that list to the contractor and ask them to price it line by line. Two quotes are only comparable when they cover the same items.
Step 3 — The code minimums
Two requirements in the International Residential Code, adopted in most of the United States, are worth knowing because they are frequently omitted from cheap quotes.
Ice barrier — IRC R905.1.2
In regions with a history of ice damming at the eaves, an ice barrier must run from the lowest edge of the roof to a point at least 24 inches inside the exterior wall line. On roofs of 8:12 or steeper, it must also extend at least 36 inches measured along the slope from the eave edge. Acceptable materials are two layers of cemented underlayment, or a self-adhering polymer-modified bitumen sheet.
The practical consequence: with a 12-inch overhang, your ice barrier must be at least 36 inches wide at the eave — a full roll width. If a quote shows a narrow strip, or none at all in a cold climate, that is a question to ask before signing.
Drip edge — IRC R905.2.8.5
Drip edge is required at both eaves and rakes on shingle roofs. It is inexpensive and often skipped on low bids. If your quote does not list it, it is either not included or not itemized, and you should find out which.
Codes are adopted locally. Your jurisdiction may use a different edition or amend it. The two requirements above are stable across recent editions, but the authority is your local building department — not this page.
Step 4 — Tear-off and disposal
Removing the old roof is real weight, and weight is money. Asphalt shingles run roughly 230 to 300 pounds per square depending on product line; architectural shingles sit at the heavier end.
For the 15-square example with one existing layer, at 250 lb per square:
| Quantity | Value |
|---|---|
| Old roofing removed | 3,757 lb |
| In tons | 1.88 tons |
| Dumpster | 10 cubic yards |
Two things follow. First, a second or third existing layer doubles or triples this — and doubles the tear-off hours. Second, disposal is usually billed by weight at the landfill, so the number above is a real cost driver that should appear somewhere in your quote.
Ask how many layers are up there before work starts. A contractor who discovers a second layer on day one and bills you for it mid-job was either careless or counting on it. A lift of a shingle at the eave answers the question in ten seconds.
Step 5 — Wage is not what you are billed
This is the part almost no cost guide explains, and it is where homeowners misread quotes.
The Bureau of Labor Statistics reports that roofers earned a mean of $27.95 per hour nationally in 2025, with a median of $26.65. That is what reaches the worker. It is not what appears on your invoice, and a contractor billing $27.95 an hour would be out of business within the year.
Two layers sit on top:
- Labor burden — payroll taxes, workers' compensation, liability insurance, paid time off. Workers' compensation for roofing is among the most expensive classifications in construction, because the work is genuinely dangerous.
- Overhead and profit — trucks, dumpsters, the estimator who came to your house, the office, warranty reserve, and the margin the business runs on.
Using 30% burden and 35% overhead-and-profit on the 15-square example:
| Step | Amount |
|---|---|
| 37.6 labor-hours × $27.95 | $1,050 |
| + 30% burden | $1,365 |
| + 35% overhead and profit | $1,843 |
So roughly $1,800 of labor on a small, simple roof. If the whole quote is $11,000, labor is about 17% of it, and the remaining $9,200 is materials, tear-off, disposal, permits, flashing, ventilation, and whatever the crew finds when the old roof comes off.
That ratio is the useful part. A quote where labor is claimed to be half the total, on a simple gable roof, is worth questioning. So is a quote so low that the labor line cannot cover legal wages plus insurance.
Step 6 — Attic ventilation
Ventilation is the item most often left off a roofing quote, and the one most likely to void a shingle warranty. Manufacturers require adequate ventilation; without it, attic heat cooks the shingles from below and moisture rots the deck.
The code sets a minimum. Under IRC R806.2, net free ventilating area must be 1/150 of the vented space. The ratio relaxes to 1/300 if either of these is true:
- A Class I or II vapor retarder is installed on the warm-in-winter side of the ceiling, in Climate Zones 6, 7 and 8; or
- Between 40 and 50 percent of the required area sits in the upper portion of the space, not more than 3 feet below the ridge, with the rest provided by eave or cornice vents.
For a 40 × 30 ft attic — 1,200 sq ft of floor:
| Ratio | Required net free area | In square inches |
|---|---|---|
| 1/150 (base) | 8.0 sq ft | 1,152 sq in |
| 1/300 (exception) | 4.0 sq ft | 576 sq in |
Split it roughly half at the ridge and half at the eaves. Intake and exhaust have to balance: ridge vent with no soffit intake pulls air from inside the house instead of from outside, which is worse than no ridge vent at all.
Net free area is a published product figure. Every vent lists its net free area per linear foot or per unit. Ask which product is being installed, look up its rating, and multiply. A quote that says "ridge vent" with no product and no length is not answering the question.
Step 7 — Lifespan and what the warranty actually covers
"Lifetime warranty" is the most misread phrase in roofing. Here are the published terms from one major manufacturer, GAF, taken from its own warranty document:
| Product tier | Defect coverage | Non-prorated period | Wind coverage |
|---|---|---|---|
| Timberline UHDZ (premium laminated) | Lifetime | 10 years | 15 years |
| Other GAF laminated shingles | Lifetime | 10 years | 15 years |
| Marquis WeatherMax (3-tab) | 30 years | 5 years | 5 years |
| Royal Sovereign (3-tab) | 25 years | 5 years | 5 years |
Three things in that table are worth pausing on.
"Lifetime" is not forever. GAF defines it as "as long as you, the original owner(s) own the property where the shingles are installed." Sell the house and it ends, subject to a transfer provision. On buildings other than single-family detached homes, the same coverage is 40 years.
The non-prorated window is short. Coverage is full for the first 10 years on laminated shingles and 5 years on 3-tab. After that the payout declines with age, so a defect discovered in year 22 of a "lifetime" warranty pays a fraction of replacement.
Wind coverage is separate and shorter. Fifteen years on laminated products, five on 3-tab. And the top wind rating usually requires a specific installation method — GAF lists 130 mph with special installation versus 110 mph without. If your quote does not say which method is being used, your wind coverage may be lower than the brochure implies.
Service life and warranty are different things. A warranty covers manufacturing defects, not wear. Roofs commonly need replacement before the warranty expires, and manufacturers do not promise otherwise. Ask what the installer's own workmanship warranty covers and for how long — that is often the more useful document, because most roof failures trace to installation, not to the shingle.
Step 8 — If insurance is paying
Many roofs are replaced on a storm claim, and the single most consequential line in your policy is whether it pays replacement cost or actual cash value.
The National Association of Insurance Commissioners gives this worked example. Two families, identical $15,000 of roof damage, identical $1,000 deductible:
| Coverage | Damage | Depreciation | Deductible | Paid |
|---|---|---|---|---|
| Replacement cost | $15,000 | — | $1,000 | $14,000 |
| Actual cash value | $15,000 | $10,000 | $1,000 | $4,000 |
A $10,000 difference on the same roof. Depreciation is calculated from the condition of the roof when it was damaged, what a new one costs, and how long that roof would normally last — so an older roof is depreciated harder.
Two more things to check in your own policy:
- Whether the wind and hail deductible differs from the main deductible. Percentage deductibles are common for storm damage, and a 2% deductible on a $400,000 dwelling is $8,000, not $1,000.
- Whether your insurer has moved your roof to actual cash value at renewal. Insurers commonly switch older roofs to ACV as they age. This happens quietly, in the renewal paperwork.
A contractor who offers to "take care of" or absorb your deductible is proposing insurance fraud, and you would be a party to it. It also tells you the quoted price was inflated by at least the deductible amount.
The same arithmetic pointed at the other two big envelope jobs gives the same answer, and more sharply: in our window replacement breakdown field labour comes to about 4.6 percent of the benchmark, because a window is mostly an object built in a factory rather than work performed at your house.
The assumptions, stated plainly
Four inputs above are marked assumption. They are ours, not measurements, and competent contractors will differ:
| Input | Our default | What moves it |
|---|---|---|
| Labor-hours per square | 2.5 | Steep pitch, multiple tear-off layers, complex valleys and dormers, two-storey access, skylights and chimneys |
| Labor burden | 30% | State workers' compensation rates, which vary widely for roofing |
| Overhead and profit | 35% | Company size, local market, warranty terms, whether they carry their own crews |
| Shingle weight | 250 lb/square | Product line; three-tab is lighter, heavy architectural is heavier |
Move them and watch the result change. At 1.5 hours per square the labor on our example falls to about $1,100; at 3.5 hours it rises to about $2,600. That spread is the honest uncertainty. Any site quoting you one confident number is concealing it.
How long it should take
Labor-hours divided by crew size gives working days. Our 15-square example is 37.6 hours — about 1.6 days for a three-person crew, which in practice means a two-day job with setup and cleanup.
A crew proposing to strip and reroof a 30-square house in a single day is either much larger than three people or cutting steps. Ask how many people will be on site and for how long, and compare it against the hours.
Questions to take to the contractor
- What roof area are you pricing, and how did you measure it? Compare against the calculator. A complex roof genuinely has more surface than a simple gable — but the gap should be explainable.
- Can you separate labor and materials? A quote that will not separate them cannot be compared with another quote.
- How many layers are coming off, and how is disposal billed? Get this settled before the first shingle moves.
- What brand and product line? Shingles vary in warranty, wind rating and weight. A quote naming no product is not a quote.
- Is ice barrier included, and how wide? Compare against the code minimum for your pitch.
- Is drip edge included at both eaves and rakes?
- What ventilation is included? Manufacturer warranties commonly require adequate attic ventilation.
- What is the price per sheet if decking is rotten? In writing, before work starts — not after the roof is open.
- What ventilation product, and what is its net free area? Multiply it out against the code minimum for your attic.
- Which wind-warranty installation method are you using? The higher rating usually requires a specific nailing pattern.
- What does your workmanship warranty cover, and for how long? Most failures are installation, not product.
- Who pulls the permit? If the answer is "we don't need one", verify that with your building department yourself.
Warning signs
- A quote that is one number with no line items. You cannot compare it, and you cannot verify it.
- Pressure to sign today for a discount that expires. Roofs are not perishable.
- Large deposit up front. Materials are typically delivered on credit; a demand for half the job in advance is a cash-flow problem you are being asked to solve.
- Door-knocking after a storm, especially from out-of-state plates. Some are legitimate; verify the licence and local address regardless.
- An offer to "cover your deductible." That is insurance fraud, and you would be a party to it.
- No proof of workers' compensation. If an uninsured worker is hurt on your roof, the exposure can reach you. Ask for the certificate and call the issuer.
What this page still does not tell you. It does not tell you what your particular contractor should charge. The benchmark is a national and regional average for one defined job, not a price for yours, and we cannot see your roof, your access, your deck condition or your local market. What the page gives you is a defensible starting position and the arithmetic behind it. Get three written quotes, check each one against the takeoff above line by line, and use the labor share to decide which questions are worth asking.
Sources and method
- Cost benchmark — Zonda, Cost vs. Value Report 2025 (38th annual edition), published through the Journal of Light Construction. Project: Roofing Replacement, Asphalt Shingles. National average job cost $31,871 for the 30-square scope summarised above; nine US Census division figures from the same edition are used to scale it. Figures read from the publisher on 31 August 2026. jlconline.com/cost-vs-value. We reproduce the national figure and derive a regional index from it; the full 119-market dataset belongs to the publisher and is worth going to the source for.
- Regions — the nine divisions are the US Census Bureau’s standard divisions, and your state is mapped to its division automatically. census.gov
- Material prices — not used, because we could not source them. Automated retrieval from Home Depot, Lowe’s, Menards, Build.com, SupplyHouse and Walmart was attempted on 31 August 2026 and refused by all six. No price on this page is a retail material price.
- Roofer wages — U.S. Bureau of Labor Statistics, Occupational Employment and Wage Statistics, SOC 47-2181, 2025 annual, national, all industries. Mean $27.95/hr, median $26.65/hr. State-level figures are published in the same dataset. bls.gov/oes
- Ice barrier requirement — International Residential Code R905.1.2: ice barrier from the lowest roof edge to at least 24 inches inside the exterior wall line; at least 36 inches along the slope where the pitch is 8:12 or greater. Verify the edition adopted by your jurisdiction.
- Drip edge requirement — International Residential Code R905.2.8.5: drip edge required at eaves and rakes of shingle roofs.
- Pitch factor — derived from the Pythagorean theorem. Verifiable by hand.
- Roofing square — 100 sq ft, the standard unit of measure in the trade.
- Bundle coverage — three bundles per square is the common packaging for asphalt shingles; some heavy products are four. Confirm on the product data sheet.
- Attic ventilation — International Residential Code R806.2: minimum net free ventilating area of 1/150 of the vented space, reduced to 1/300 where a Class I or II vapor retarder is installed in Climate Zones 6-8, or where 40-50% of the area is in the upper portion not more than 3 ft below the ridge.
- Shingle warranty terms — GAF Shingle & Accessory Limited Warranty (document RESWT160L), publisher's own terms. Other manufacturers publish comparable documents; read the one for the product you are quoted.
- Insurance example — National Association of Insurance Commissioners, consumer guidance on replacement cost versus actual cash value. content.naic.org
- Labor-hours per square, labor burden, overhead and profit, shingle weight — assumptions set by Home Repair Ledger and adjustable in the calculator. They are not measurements and are not sourced.
Wage figures are updated when BLS publishes a new OEWS release. Code citations are to the model code; your jurisdiction governs.
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