Three roofers come out, and you end up with three numbers that are thousands of dollars apart. It’s tempting to grab the lowest one and move on. But the number is only as good as what’s written behind it. A solid roofing estimate spells out exactly what you’re paying for, so you can compare bids fairly and know what you’ll get on the day the crew shows up. Here’s what a good one includes, and the red flags that should make you slow down.
Why the details matter more than the total
Two estimates can both say “replace roof” and describe very different jobs. One might include new underlayment, ice and water shield, new flashing and vents. The other might reuse old flashing and leave decking repairs as a surprise charge later. The cheaper bid often isn’t cheaper once the job is done. A detailed roof estimate protects you from that, because everything that matters is in writing before work starts.
What a written roofing estimate should include
Every bid you get should cover these items clearly. If one is missing, ask for it in writing.
- Scope of work. Full tear-off or a layover, how many layers come off, and which parts of the roof are included (garage, porch, dormers).
- Materials by name. The shingle brand and product line, the color, and the underlayment, ice and water shield, starter strip and ridge cap.
- Flashing and ventilation. Whether chimney, wall and valley flashing gets replaced, and what’s happening with ridge, box or soffit vents.
- Decking. The price per sheet for rotted plywood, since nobody can see the decking until the old roof is off.
- Cleanup and disposal. Dumpster, magnet sweep for nails, and protection for landscaping and siding.
- Permits. Who pulls the permit and who schedules the final inspection with your city.
- Warranty. Both the manufacturer’s material warranty and the contractor’s workmanship warranty, with the length of each.
- Payment terms. Deposit, when the balance is due, and any financing.
- Timeline. A realistic start window and how many days the job should take.
Red flags to watch for
Most roofers are honest, but a few warning signs show up again and again in bids that go wrong:
- A single line that just says “new roof.” No materials, no scope, no warranty.
- Pressure to sign today. “This price is only good if you sign now” is a sales tactic, not a roofing fact.
- A large cash deposit up front. A reasonable deposit covers materials. Paying most of the job before work starts puts all the risk on you.
- No license or insurance paperwork. In Michigan, roofing contractors should be licensed by the state and carry liability and workers’ comp insurance. Ask for proof.
- Storm chasers. Out-of-town crews who knock on doors after hail or wind and may be gone when a warranty issue comes up.
Want an estimate you can actually compare?
T&M Roofing gives every customer a free, fixed written quote that lists materials, scope and warranty line by line. Already have a written estimate? We will beat it.
Get a Free Estimate or call (313) 600-4538
How to compare two bids side by side
Lay the estimates next to each other and go line by line. Check that both include the same tear-off, the same grade of shingle, the same underlayment and the same flashing work. If one bid is far lower, look for what’s missing, usually flashing, ventilation, or a vague decking allowance. Then compare warranties: a longer workmanship warranty tells you how confident the roofer is in their own install.
If something is unclear, ask. A good contractor will happily explain each line. You can also run your own numbers with our instant roof quote tool to see if a bid is in a reasonable range.
Questions to ask before you sign
- Is this a fixed price, or can it change once the old roof is off?
- What’s the price per sheet if you find rotted decking?
- Will you replace the flashing and vents, or reuse them?
- Who pulls the permit, and who handles the final inspection?
- Who will be on site each day, your own crew or subcontractors?
- What does your workmanship warranty cover, and for how long?
What T&M Roofing puts in writing
Every T&M estimate is free, written and fixed. It lists the full scope, the exact materials, decking pricing, cleanup, and our 10-year labor warranty on top of the manufacturer’s coverage. If you’re watching the budget, we also offer roof financing. And when you’re ready, our roof replacement process starts with a free inspection with photos, so you see what we see.
Frequently asked questions
How many roofing estimates should I get?
Two or three is usually enough. More than that tends to add confusion rather than clarity, especially if the bids aren’t written to the same scope.
Should a roofing estimate be free?
For a standard home, yes. Most reputable roofers in Metro Detroit, including T&M Roofing, inspect the roof and write the estimate at no charge.
Why do roofing estimates vary so much?
Differences in materials, how much flashing and ventilation work is included, decking allowances, crew experience and warranty length all change the price. That’s why comparing line by line matters more than comparing totals.
Can the price change after the job starts?
It shouldn’t, except for items the estimate lists as variable, like rotted decking priced per sheet. Ask for a fixed price in writing.
T&M Roofing writes clear, fixed estimates for homeowners in Detroit, Dearborn, Livonia, Southfield and across Metro Detroit. Call (313) 600-4538 to book your free inspection.
Helpful outside resources: National Roofing Contractors Association – consumer information · Michigan LARA – protect your home improvement projects