Editorial standards set by Stu Clark, a UK-trained plumber who ran his own plumbing and bathroom renovation business for 10 years before founding Top5HomePros.
Roof quotes vary widely mainly because of what is included beyond the shingles themselves: tear-off and disposal of the old roof, underlayment quality, flashing and decking repairs, and the manufacturer's warranty being offered. Two quotes for the same square footage can differ by thousands simply because one includes a full tear-off and the other does not.
Why the Same Roof Can Get Wildly Different Quotes
A roof quote is not just a price per square foot of shingle. It is a bundle of decisions: whether the old roof is fully removed or layered over, what underlayment is used, whether damaged decking is replaced or worked around, and what warranty backs the finished job. A lower quote is often a lower quote for less work, not simply a better deal.
How we actually vet the roofers on our lists
When we research roofers for our Top 5 lists, we look specifically for evidence of manufacturer certification, since major shingle brands only certify installers who meet their training and workmanship standards, and that status is independently verifiable rather than a claim the roofer makes about themselves. We also weigh how a business responds to a bad review, since a roof problem that surfaces after installation is exactly the moment a good roofer's response actually matters.
Tear-Off Versus Roofing Over the Old Layer
Some quotes install new shingles directly over the existing layer, which is faster and cheaper but can trap moisture and hide underlying decking damage. A full tear-off costs more upfront but lets the contractor actually inspect and repair the decking underneath, which is usually the right call unless your roof is genuinely in good condition already.
Underlayment and Flashing Quality
Underlayment is the water barrier beneath your shingles, and it is invisible once the job is done, which makes it an easy place for a lower quote to cut corners. Ask specifically what underlayment is being used and whether flashing around chimneys, vents and valleys is being replaced or reused. Reused flashing is one of the most common sources of a leak years down the line.
What the Warranty Actually Covers
A manufacturer's material warranty and a contractor's workmanship warranty are two separate things, and a quote should specify both clearly. A material warranty covers defective shingles. A workmanship warranty covers the contractor's own installation errors, and it is only as good as the company still being in business years later to honor it.
Questions to Ask Before You Compare Quotes Side by Side
- Is this a full tear-off or an overlay? Make sure every quote you compare is for the same scope.
- What underlayment and flashing are included? Get this in writing, not just verbally described.
- What does the workmanship warranty cover, and for how long? A vague answer here is a real red flag.
- Is the contractor manufacturer-certified for the shingle brand being used? This is independently checkable with the manufacturer.
The National Roofing Contractors Association is a useful reference point for the kind of questions a professional, established roofer should be able to answer without hesitation.
Getting quotes that are actually comparable starts with hiring roofers worth comparing in the first place. Our Top 5 roofers list is independently researched town by town, from St. George, UT to Bozeman, MT to Center City, Philadelphia.