Roofing is usually priced per roofing square, per job, or per square plus line items for extras. Learning how to price roofing jobs starts with a good estimate: you cannot set a fair price on a roof you have not measured and inspected. Whichever way you quote, check it against the real cost of the job.
How to estimate a roofing job, step by step
An estimate is the count of everything the job will use: roof area, material, crew time and trips. The price comes after. Do these six steps in order, and write each number down so you can check it after the job.
1. Measure the roof in squares
A roofing square is 100 square feet of roof surface. Start with the flat area the roof covers from above, called the plan area. Include the overhangs, not just the walls. You can measure on the roof, from the ground with the eave lengths, or from an aerial report. If you use an aerial report, still walk the roof or look closely from a ladder before you send the price.
While you measure, also take lengths in feet of the eaves (the bottom edges), rakes (the sloped edges at the gable ends), ridges, hips and valleys. Those lengths decide how much drip edge, starter strip, ridge cap and valley material you need. Count every pipe, vent, skylight and chimney too. Each one is flashing work.
2. Apply the pitch factor
Pitch is how steep the roof is, written as rise over 12 inches of run. A 6/12 roof rises 6 inches for every 12 inches across. A sloped roof has more surface than the flat area under it. Multiply the plan area by the pitch factor to get the real surface area.
| Pitch | Pitch factor (multiply plan area by) |
|---|---|
| 4/12 | 1.054 |
| 6/12 | 1.118 |
| 8/12 | 1.202 |
| 10/12 | 1.302 |
| 12/12 | 1.414 |
These factors are plain geometry, not survey data: the square root of (rise × rise + 144), divided by 12. They correct the area only. A steep roof also slows the crew, and that belongs in the labor step, not here.
3. Add a waste allowance
You always order more than the measured area. Shingles get cut at hips, valleys, rakes and around every pipe, vent and skylight. A plain gable roof wastes less than a cut-up roof with dormers and many valleys. Keep your own waste figure for each roof type, and check it against what you ordered and returned on past jobs. Add starter and ridge cap as separate items, since they are bought by the length, not the square.
4. Count the tear-off layers and check the decking
Tear-off means stripping the old roofing down to the wood deck. Look at the edge of the roof or lift a shingle at the rake to count the old layers. Each layer adds tear-off hours, weight and dump fees. Go into the attic if you can. Stains, soft spots or daylight through the boards point to rotten decking. Since you cannot see all of it before the roof is open, price decking per sheet in the contract instead of guessing a total.
5. Build the material list
Turn the squares and lengths into a full list: shingles or other roofing, underlayment, ice and water membrane where your area needs it, drip edge, starter, ridge cap, vents, flashing, pipe boots, nails and sealant. Add the dumpster or disposal trips and any permit. Get current prices from your supplier on the day you estimate, not from last season.
6. Turn the work into crew days
Estimate labor as crew days, not a guess at a dollar figure. Use your own past jobs: how many squares your crew finished per day on a roof with the same pitch, height and number of layers. Add set-up and safety time, clean-up, and drive and loading time each day. Then multiply total person-hours by the full cost of one person-hour, including payroll taxes and workers' compensation, not just the wage. Our guide on estimating labor hours for a job goes deeper on this step.
After the job, compare the real hours, waste and dump trips with your estimate. In CrewBrain, the crew clocks in and out from the app and hours are tracked by job, so the next roof estimate can start from what really happened.
Price by the roofing square, but build it from cost
Quoting per square makes bids easy to compare. But the per-square rate should be the answer to a calculation, not the starting point.
Build it in this order:
- Measure the roof surface, not the floor area. Pitch, hips, valleys and dormers add area.
- Add the cost of material, including waste.
- Add labor hours for tear-off, install and clean-up, at the full hourly cost.
- Add disposal, permits, equipment and fuel.
- Add your margin, then divide by the number of squares to get the unit rate.
That rate only fits roofs like the one you measured. Use it as a check on other quotes, not as a rule for every roof.
Tear-off, disposal and what is under the shingles
Tear-off is where quotes go wrong. The old layers, the dump fees and the truck trips all cost money, and you do not know the real weight until the roof is open.
- Count the layers of old roofing. Each one adds labor and disposal.
- Price dump fees and trips from what your local facility actually charges you.
- Allow for rotten decking. Put a price per sheet of replacement in the contract.
- Ask about skylights, chimneys and vents. Each adds flashing work.
Rotten wood is the classic surprise. If your quote does not say how it will be charged, you pay for it.
Pitch, height and safety time
Steep and tall roofs are slower and riskier. Crews spend time on set-up: ladders, harnesses, anchors, scaffolding and sometimes a lift. That time is paid labor even though no shingles go on.
Price it directly. A steep pitch slows every task, and a second storey adds material handling. A low-slope roof and a steep two-storey roof can have the same area and very different labor cost. Do not use one rate for both.
Remember the cost of cover too. Roofing is high-risk work, and insurance and workers' compensation belong in your hourly cost, not in your hopes.
Material waste, supplier changes and weather
Waste depends on roof shape. A simple gable wastes less than a roof full of hips, valleys and cut-ups. Set a waste allowance for each roof type, then compare it with what you actually ordered and returned.
Material prices change. Put an expiry date on every estimate and say that supplier increases after that date can be passed on. On longer jobs, order and lock in materials early if you can.
Weather delays cost money too. A crew that shows up and cannot work still gets paid, and a half-open roof needs tarping. Add a weather allowance to the schedule, and on big jobs add a clause for standby or return trips.
Mistakes that quietly cost you money
- Using last season's material cost without checking with the supplier.
- Pricing tear-off as a flat figure without counting layers.
- Having no clause for rotten decking, so you pay for it.
- Leaving out permits, dumpster rental, dump trips and fuel.
- Ignoring warranty callbacks. A leak call a year later costs a truck, a crew and a day. Set aside a share of every job for it.
- Quoting from aerial measurements without checking pitch and complexity.
When to say no or raise the price
Roofing leaves little room for guessing. Raise the price or decline when:
- The roof is steep, tall or hard to reach and the customer expects your standard rate.
- The structure looks bad and the customer will not agree to a decking clause.
- The start date forces you into poor weather or overtime.
- The customer wants the lowest price and rejects materials you are willing to warrant.
- Payment terms leave you carrying the material bill for weeks.
A cheap job that comes back for repairs costs more than the job you turned down.
Test the price before you send it
Take the total from your build-up and divide it by the number of squares. Does that rate cover labor, material, disposal and your margin? Now ask what happens if the job runs one day longer. If that wipes out the profit, add a buffer.
Run the same job through the example on this page, using your own hours and costs. When you finish a roof, compare actual hours, waste and dump trips to the estimate. Fix the gap in your next quote. CrewBrain tracks the real cost of each job so you can see which jobs earn their price.
A worked example: tear-off and re-roof of a small single-storey house roof, including disposal
| Item | How it is worked out | Amount |
|---|---|---|
| Labor | 4 people × 17 hours (including drive time) × $38 per hour | $2,584 |
| Materials | Shingles, underlayment, flashing, vents and disposal | $2,400 |
| Vehicle and fuel | Truck time and fuel for this job | $180 |
| Job costs | $5,164 | |
| Price at a 35% margin | $5,164 ÷ 0.65 | $7,945 |
| Left after job costs | $7,945 − $5,164 | $2,781 |
Where the price goes in this example
Every dollar of the price, split into the costs it covers and what is left over.
- Labor $2,584 (33%)
- Materials $2,400 (30%)
- Vehicle and fuel $180 (2%)
- Left after job costs $2,781 (35%)
The whole bar is the price the customer pays: $7,945. Illustrative numbers, built from the table above.
Hourly cost per person is the full cost of an hour, including taxes, insurance and workers' compensation, not just the wage. Materials includes shingles, underlayment, flashing and disposal. These numbers are an illustrative example of the method. They are not a price list, and not a promise of what your jobs will earn.
To turn this into a per-square rate, divide by the measured squares from the estimate: $7,945 ÷ 14.5 squares is about $548 per square, for this roof only. Note that a 35% margin is not the same as adding 35% to cost. Adding 35% to $5,164 gives only $6,971, and about 26% of that price is left after job costs. Your overhead (office, ads, software and your own pay) is paid from what is left, so the gap matters. See profit margin vs markup for the full explanation.
Try it with your own numbers
Job costs means crew time (with drive time), materials, vehicle and fuel. Hourly cost per person is the full cost of an hour, including payroll taxes and insurance, not just the wage. This is a simple calculator, not a quote.
Keep going
- CrewBrain for roofing companies: how the software handles quoting, scheduling and crew time for this trade.
- How to price a service job: the five-step method behind every page in this series.
- Job price calculator: the same calculator as above, on its own page.
- Price increase calculator: see how many customers you can lose before a raise stops paying.
- How to price junk removal jobs
- How to price moving jobs
- How to price snow removal jobs
- What is a good profit margin for a service business?
- Labor burden calculator: work out the full cost of one person-hour on your crew.
- How to estimate labor hours for a job
- How to quote a job professionally
- All pricing guides by trade
Questions owners ask
How do you estimate a roofing job?
Measure the plan area and multiply by the pitch factor to get squares. Add a waste allowance, count the old layers and check the decking. Build the material list, then estimate crew days from your own past jobs. Cost all of it, and only then add your margin.
How do you calculate roofing squares with pitch?
Take the flat area the roof covers, including overhangs, and multiply it by the pitch factor. For a 6/12 roof the factor is 1.118. Divide the result by 100 to get squares, then add waste before you order.
How do I price a roof replacement per square?
Work out the full cost of the job first: material with waste, labor hours, disposal, permits and fuel. Add your margin, then divide by the number of squares. Use that rate only for similar roofs.
How do I charge for rotten decking found during a job?
Put a price per sheet of replacement decking in your contract before work starts. Tell the customer that the final count is only known once the old roof is off.
How much waste should I add to a roofing quote?
Base it on the shape of the roof, since hips, valleys and dormers create more offcuts. Start with a set allowance for each roof type, then adjust it using what you actually ordered and returned.
How do I protect myself from material price increases?
Put an expiry date on each estimate and a clause that allows supplier increases after it. On larger jobs, order or lock in the material early.