How to compare roofing quotes without comparing apples to oranges

Why two totals are rarely comparable

Two contractors can look at the same roof and price two different jobs. One quotes a patch and a return visit. The other quotes a larger repair that removes the cause. One includes disposal and permits; the other leaves them out and adds them later. The totals arrive a week apart, look like a $600 difference, and describe scopes that are not the same shape.

This is not usually dishonesty. It is what happens when a price is written before the scope is written down. Your job in comparing is to make the scope visible first.

Step 1: get the scope in writing

Ask every contractor for the same four things in the quote document: what will be removed, what will be installed (with material and quantity), what is excluded, and what warranty applies. A quote that cannot answer those four is not ready to be compared.

• Quantities: linear feet of flashing, square feet of shingles, number of panels, number of leak locations.
• Materials: product family and, where it matters, the specific product.
• Method: welded, adhered, mechanically fixed, replaced or sealed.
• Access and protection: what is being used, and who is responsible for it.
• Disposal: who removes debris, and where it goes.
• Permits: who applies, and whether the fee is in the total.
• Tax: included or added.

Step 2: check the quantities against each other

If one quote covers 60 square feet and another covers 180, the second is not necessarily overpriced — it may be repairing a larger area because it includes material that was damaged adjacent to the visible failure. But the difference has to be explained, not just priced.

Step 3: read the exclusions before the price

Exclusions are where the real difference lives. “Decking replacement if found soft, at additional cost” can turn a mid-hundreds repair into a much larger invoice, and it is the single most common reason a final bill exceeds the quote.

You are not trying to remove every exclusion — a contractor cannot know what is under the shingles until they open them. You are trying to know the unit price for the most likely extra before you sign, so the surprise is a number rather than an argument.

Step 4: compare price on a named basis

Once the scopes line up, compare totals against a named basis: for example, the lowest total, or the quote you consider most complete. State it out loud — “Quote B is 22% higher than Quote A” — and then ask what the extra buys. Sometimes it is a better detail, a longer warranty, or a larger area. Sometimes it is nothing you can name.

• Absolute difference: the dollar gap between totals.
• Percentage difference: the same gap expressed against a named basis quote.
• Scope difference: what the higher price actually includes that the lower one does not.

The quote comparison tool calculates absolute and percentage differences against a basis you select, and flags the inclusion rows that differ. It deliberately does not score contractors or recommend one.

Step 5: check the things a price cannot tell you

1. Registration or licence: check with your state or local licensing authority, not with the contractor's own paperwork.
2. Insurance: ask for a certificate of insurance and verify it with the insurer. If subcontractors are used, ask about their cover too.
3. References: ask for two recent jobs of the same type, and ask those customers whether the scope matched the invoice.
4. Payment schedule: be cautious of large deposits before work starts, and never pay the full amount in advance.
5. Contract terms: a written contract should name the scope, the price, the payment schedule, the warranty and the cancellation terms.

Making the decision

There is no rule that the cheapest or the most expensive quote is right. A useful decision names three things: the scope you are buying, the warranty behind it, and the price for the most likely extra. If two quotes give you all three, you can choose between them on judgement rather than guesswork.