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Free roofing estimate calculator: price a roof by the square

Measure each roof section's footprint, pick the pitch, and get the roof squares. Then price the tear-off by layer, the shingles with your waste factor, underlayment, flashing and vents, a decking allowance per sheet, the permit, and the dumpster, and see the total, the deposit, and the price per square. Print it as a one-page quote. No signup, and nothing you type leaves your browser.

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Set your prices once, then type in each roof. Jump to the price, how to measure and price a roof, the pitch factor table, or what a roofing estimate should include. Texts for first contact, inspections, and follow-ups are on the roofing text templates page.

Sample prices The prices below are made up so you can see how it works. Type in your own prices.

1. Your business and the customer

2. Your prices

Per square

Decking, dumpster, labor, and markup

Flashing and vents

Each item is figured from the roof lines in step 3. Pieces = the length ÷ what one piece covers, rounded up. They add up at your cost, then your markup is added, and the quote shows them as one line with this name:

3. This roof

Roof sections

Footprint: the length and width of the area under that part of the roof, eaves included, as you'd measure it from the ground or a satellite photo. The pitch factor turns it into roof surface. Roof surface: you measured the roof planes themselves, so no factor is applied. Type an area instead of length and width if you have it. Layers off: 2 for two layers, 0 for an overlay.

Roof lines (feet) and pipe boots

Waste, decking, permit, dumpster, labor

Other items

Chimney flashing, a skylight, gutters, or a small repair. Type your cost and leave Price each blank to add your markup, or type the price yourself. A blank quantity counts as 1.

4. The price

5. Notes for the quote

Put the example notes back

Quote text to copy

Send this with the PDF, or read it over the phone. It fills in from the calculator, so check it before you send.

How to measure and price a roof

1. Measure the footprint of each section. Length and width of the house, garage, porch, or dormer, eaves included. A tape on the ground or a satellite photo works for most homes.
2. Pick the pitch. Rise per 12 inches of run, from a pitch gauge or the gable. The pitch factor turns the footprint into roof surface: 6/12 adds about 12%.
3. Get the squares. Footprint × pitch factor ÷ 100, added up and rounded up. Count the layers to come off while you're on the roof.
4. Measure the roof lines. Eaves, rakes, ridge, hips, and valleys in feet, and the pipe boots. They set the drip edge, ridge vent, and flashing.
5. Price it per square, then add the rest. Tear-off by layer, shingles with waste, underlayment, flashing and vents at cost plus markup, a decking allowance, the permit, and the dumpster. Check the price per square against your past jobs.

Pitch factor table

Roofing prices vary a lot by region, material, and season. Set yours from your own costs and past jobs, and change them in step 2.

How the math works

• Section squares = length × width (or the area you typed) × the pitch factor ÷ 100, to 2 places. A Roof surface section skips the pitch factor.
• Roof squares = the sections added up, rounded up to the nearest whole square (or the step you set). Tear-off squares and steep squares are rounded up the same way.
• Tear-off = first-layer squares × the first-layer price, plus the squares of each extra layer × the extra-layer price.
• Shingles = roof squares + waste %, × the price per square. Underlayment and the steep charge = their squares × their price.
• Flashing and vents = for each item, the length ÷ what one piece covers, rounded up, × the cost each; all added up, plus your markup.
• Decking = sheets × price per sheet. Permit at cost. Dumpsters = count × price. Extra labor = hours × rate.
• Price = all the lines, raised to your minimum job if lower, rounded to the nearest dollar amount you picked. Total = price + sales tax. Deposit = total × deposit %.
• Price per square = the price before tax ÷ the roof squares.

The made-up sample is the same roof as the roofing estimate template: a 50 × 36 ft house and a 22 × 14 ft garage, both 6/12 (factor 1.118) with two layers to come off. That's 20.12 + 3.44 = 23.56 squares, rounded up to 24. Tear-off is 24 × $70 ($1,680.00) plus 24 × $35 for the second layer ($840.00). Shingles are 24 squares + 10% = 26.4 × $330 ($8,712.00), and underlayment is 24 × $50 ($1,200.00). Flashing and vents come to $1,000.00 at cost (26 pieces of drip edge on 256 ft of eaves and rakes, 18 pieces of ridge vent on 72 ft, 3 pipe boots, and $300 of step flashing, sealant, and fasteners) + 25% = $1,250.00. Add 6 sheets of decking at $85 ($510.00), the $185.00 permit, and a $525.00 dumpster for $14,902.00, or $620.92 per square. A 30% deposit is $4,470.60.

Customer said yes? Write it up with the roofing estimate template or the blank free estimate maker, bill it with the roofing invoice template, and give a receipt for the deposit with the roofing receipt template. Found more rotted decking than the allowance? Put it in writing with the free change order maker.

What a roofing estimate should include

A clear estimate answers the homeowner's questions before they ask, makes your bid easy to compare with others line for line, and gives you something to point to when the deck turns out worse than it looked. Put these on every roofing quote:

• Who and where. Your business, phone, email, and license number if your state requires one, the customer's name, and the property address.
• Roof size in squares. One square is 100 sq ft of roof. Put the squares on the tear-off, underlayment, and shingle lines so the customer can compare bids line for line.
• Tear-off, by layer. Give each layer its own line. A second or third layer means more labor and more weight in the dumpster.
• Shingles with the waste factor. Show it ("24 sq + 10% waste") so the bigger number on the shingle line doesn't look like a mistake.
• Underlayment, flashing, and vents. Name what goes under and around the shingles: underlayment, ice and water shield, drip edge, step flashing, pipe boots, and ridge vent.
• Decking as an allowance, per sheet. You can't see rotted decking until tear-off. Include a set number of sheets at a per-sheet price, and say unused sheets come off the final bill.
• Permit, dumpster, and cleanup. The permit at what the city charges, who schedules the inspection, the dumpster, and how you pick up nails.
• Deposit and balance. The deposit to book the job and order materials, and when the balance is due. Check your state's deposit limit first.
• Warranty and how long the price holds. The shingle maker's warranty, your workmanship warranty, and how long the quote is good for, since material prices move.

Roofing estimate questions

How do you calculate roofing squares?

A square is 100 square feet of roof surface. Measure each section's footprint (length times width, eaves included), multiply by the pitch factor for that section's slope, add the sections, and divide by 100. Or measure each roof plane on the roof and add those up. The sample house is 50 by 36 ft plus a 22 by 14 ft garage, both 6/12: 2,108 sq ft of footprint times 1.118 is about 2,356 sq ft, which rounds up to 24 squares.

What is a roof pitch factor?

Pitch is how many inches the roof rises for every 12 inches it runs, such as 6/12. A sloped roof has more surface than the ground it covers, and the pitch factor is how much more: the square root of 1 plus (rise / 12) squared. It's 1.054 for 4/12, 1.118 for 6/12, 1.202 for 8/12, and 1.414 for 12/12. The table on this page lists them.

How much waste should I add for shingles?

Many roofers add about 10% for a simple gable roof and 15% or more for hips, valleys, and dormers, to cover cuts, starter, and ridge caps. The waste goes on the shingle line only. Tear-off and underlayment are priced on the roof squares. The 10% in the sample is an example, so use what your own jobs show.

How should I price tear-off with more than one layer?

Price the first layer and each extra layer on their own lines. Extra layers take more labor and fill the dumpster faster, and many homeowners don't know they're there. In step 3, type the layers to come off for each section: 2 adds a second-layer line, and 0 means an overlay with no tear-off.

How do I handle rotted decking on a roofing estimate?

Use an allowance. Include a set number of sheets at a per-sheet price, such as up to 6 sheets at $85 each, and say in your notes that the customer pays only for the sheets you use and that you'll show them before going past the allowance. A 4 by 8 ft sheet covers 32 sq ft.

How much deposit should a roofer ask for?

Many roofers take a deposit to order materials and hold the date. Some states cap deposits on home improvement work. California, for example, limits most to 10% or $1,000, whichever is less. Check your state's rules before you pick a number. The sample uses 30% as an example. This is general information, not legal advice.

Do I charge sales tax on a roof replacement?

It depends on your state. In some states a roof replacement is a real property improvement and the roofer pays tax on the materials instead of charging it, while others tax the job or the materials on the bill. This calculator applies the rate to the whole price. Check with your state's revenue department or an accountant. This is general information, not tax or legal advice.