Roof Replacement Cost: Tear-Off, Decking, Permits

What is actually in a roof replacement estimate

A re-roof bid is not one line item. It is a demolition job, a waterproofing job, and an installation job stacked on top of each other, and each one carries its own labor.

At the rates this tool uses, a 1,200 sq ft roof surface carries roughly 42 labor hours, or about $2,940 in labor, plus about $420 in consumables. Material sits on top of that: at the basic tier the tool models $2.20/sq ft, mid-range $3.90/sq ft, and premium $7.50/sq ft, which lands a 1,200 sq ft job somewhere between roughly $6,000 and $12,400 all-in before decking repairs or permit fees. Costs vary by region and by season, so treat every figure here as a planning baseline rather than a quote.

Roofers usually quote in squares rather than square feet. One square is 100 sq ft, so a 1,200 sq ft roof is 12 squares. Divide a per-square price by 100 before comparing it against a per-square-foot estimate.

• Tear-off of the existing roofing down to the deck, plus dumpster and disposal fees
• Deck inspection and any sheathing replacement, almost always billed separately
• Drip edge and synthetic felt underlayment across the field
• Shingle or panel installation, ridge cap ventilation, and step and valley flashing

Labor and consumables in this dataset are the same per square foot at every tier, so upgrading materials raises your total but not your install cost.

What drives roof replacement cost up or down

Square footage is the starting point, but the same 1,200 sq ft of roof can price very differently depending on what the crew has to work around.

Pitch is the biggest single multiplier. A walkable roof lets a crew move fast. A steep roof means harnesses, roof jacks, and slower production, which shows up as more hours against the same area. Height matters for the same reason.

Complexity is the second driver. Every valley, dormer, skylight, chimney, and pipe boot is a place where water can get in, so each one gets flashed by hand. A simple gable roof with two planes is far cheaper per square foot than a cut-up roof with the same footprint.

• Roof pitch, and whether the crew can walk it safely without staging
• Number of layers being torn off, since two layers means twice the demolition and disposal
• Valleys, dormers, chimneys, skylights, and pipe penetrations that need flashing
• Material tier, from architectural shingles up through standing seam metal and synthetic slate

Decking surprises: the cost nobody can quote in advance

The plywood or plank sheathing under your shingles is invisible until the tear-off. If water has been getting past a failed flashing for a few seasons, sections of it will be soft, delaminated, or rotted through, and they have to be replaced before anything goes back on.

No honest roofer can tell you how much decking is bad from the ground. What a good roofer can do is quote a unit price up front, so the surprise becomes a known rate instead of a negotiation while your house is open to the sky. Ask for the per-sheet price to replace 4x8 sheathing in writing, and ask what happens if the entire deck has to come off.

Budget for some decking work rather than none. A contingency of 10 to 15 percent of the job total is a reasonable cushion on an older roof, and anything unused stays in your pocket.

Be cautious with a bid promising unlimited decking replacement at no extra cost. That risk is priced in somewhere, usually as a higher base number or a thinner spec.

Permits, licensing, and code requirements

Re-roofing almost always requires a building permit, and in most places it requires a licensed and insured roofing contractor to pull it. Permit fees, inspection scheduling, and any code-triggered upgrades are real line items, so ask whether the bid includes them.

Codes vary by jurisdiction, and a re-roof is often the moment older work has to be brought current. Common triggers include ice barrier requirements in cold climates, minimum attic ventilation ratios, drip edge, and limits on how many roofing layers a structure may carry. Your building inspector, not your contractor, has the final word on what your local code demands.

Verify the license and insurance yourself rather than accepting a photocopy. Check the license number with your state or municipal licensing board, and ask the carrier to send the certificate directly. Workers compensation matters most, because an uninsured crew member hurt on your roof can become your exposure.

• Confirm who pulls the permit and whether the fee is included or billed through
• Verify the contractor license number directly with the issuing authority
• Request a certificate of insurance from the carrier, including workers compensation

How an insurance claim changes the math

If your roof failed from a covered event such as hail or wind, your insurer may pay for the replacement, and the accounting works differently from a cash job. Policies settle on either actual cash value, which deducts depreciation for the age of the roof, or replacement cost value, which pays that depreciation back after the work is completed and documented. Check which one you carry before you assume a number.

You still owe your deductible. Any contractor who offers to waive it, absorb it, or bill around it is proposing something that ranges from a bad idea to insurance fraud depending on your state. That is a reason to end the conversation.

Insurance scopes come from an adjuster inspection and frequently miss what the crew finds later, including decking. That is what a supplement is for. Photograph the tear-off and have your contractor document any added scope in writing while the roof is still open.

• Read whether your policy pays actual cash value or replacement cost value
• Have the contractor document decking and flashing findings in writing during the work
• Do not sign a blanket assignment of benefits without understanding what you are handing over

Run the estimate on this page independently of the insurance scope. A second number built from different assumptions gives you something concrete to point at when you ask for a supplement.

DIY versus hiring a roofing contractor

This is the one category where the answer is not close. Roof work is a leading fall hazard in residential construction, and a fall from a single-story eave is enough to cause permanent injury. Add a tear-off, loose debris underfoot, a pitched walking surface, and a full day of carrying bundles, and the risk is not something a weekend of research offsets. Do not DIY a roof replacement.

The legal picture points the same direction. Most jurisdictions require a licensed contractor and a permit for a re-roof, unpermitted roofing tends to surface as a problem at resale, and manufacturer shingle warranties are commonly void without a qualifying installation. If you are financing the work or claiming it on insurance, self-performed labor may not qualify at all.

What you can usefully do is everything that is not on the roof. Measure your footprint from the ground to sanity-check the square footage in a bid, compare bids line by line on identical scope, get the decking unit price in writing, and photograph the attic for water staining before anyone starts.

• Get at least three bids written to the same scope, material tier, and underlayment
• Ask each bidder for the per-sheet decking price and the disposal method in writing
• Confirm ventilation work is included, since attic airflow drives how long the new roof lasts

Roofing is licensed, permitted work performed at height. Hire a licensed and insured contractor, and never let anyone work on your roof without fall protection.