Reading a Roof Estimate: The Line Items That Decide Quality

You have three quotes. The cheapest is well below the others. Every one says it is replacing your roof. It is genuinely hard to know what you are comparing, because the differences sit in items that are easy to leave vague.

Here is what to look for, in roughly the order it matters.

1. Tear off or overlay

An overlay puts new shingles over the old ones. It is cheaper and faster. It is also, in most situations, the wrong answer.

With an overlay nobody inspects the deck, so rot and damage stay hidden under the new roof. You add significant weight. The new shingles sit on an uneven surface and wear unevenly, and they run hotter because the old layer insulates them from below. In our climate that last point is not trivial.

If a quote is dramatically cheaper, check this line first. It is the most common reason.

2. What happens if the deck is damaged

Nobody can see the deck until the old roof is off. A good estimate says clearly what happens then: a rate per sheet of plywood, and a commitment to show you before replacing it.

A quote silent on this is not protecting you. It is leaving room for a conversation you will have later, with the roof open, at whatever price is quoted in the moment.

3. Underlayment

Underlayment is the layer between deck and shingles, and it is the last defense when water gets past the surface. Quality and type vary a great deal, and so does price.

The estimate should name the product. "Underlayment" on its own tells you nothing. This also matters for fire rated assemblies, where the underlayment is part of what earns the rating.

4. Ventilation

If ventilation is not mentioned anywhere, that is a flag. A roofer who has assessed your roof properly will have formed a view on whether the attic breathes, because it directly affects how long the new roof lasts.

We wrote about why this matters so much here in why Valley roofs age faster.

5. Flashing

Most roof leaks are not holes in the field of the roof. They are failures where the roof meets something else: a chimney, a wall, a vent, a valley. Flashing handles those junctions.

Reusing old flashing saves money now and is a common source of leaks in an otherwise new roof. The estimate should say whether flashing is being replaced.

6. Disposal, protection and cleanup

A tear off produces a startling volume of waste. Is disposal included? Is the landscaping protected? Is there a magnetic sweep for nails at the end?

These sound like small items. Ask anyone who has found roofing nails in their lawn for the following two years.

7. The warranty, split in two

There are always two, and they are different things:

• Manufacturer warranty covers the materials. Stronger versions often require installation by a certified contractor and correct system components.
• Workmanship warranty covers the installation and comes from the contractor. This is the one that depends on the company still existing in eight years.

Ask for both in writing. Our warranty page sets out how ours work.

8. License, insurance, and who is on the roof

Confirm the license number and that it is active. Confirm liability cover and workers compensation. If a crew member is injured on an uninsured job, that can become the homeowner's problem.

Ask whether the crew are employees or subcontractors. Either can be fine. Knowing the answer tells you who is accountable.

9. Compliance

Ask directly how the proposed roof meets current requirements for your address, covering energy rules and, if relevant, fire hazard zone requirements. A contractor who works in your area will answer immediately.

The real question

Not "which is cheapest" but "are these quotes describing the same job". Usually they are not. Once you line up tear off, deck, underlayment, ventilation, flashing and warranty, the gap often stops looking like a bargain and starts looking like a different piece of work.

We are happy to walk through our estimate line by line and explain why each item is there. Ask for a quote and bring your other ones. We will tell you honestly if someone else has offered you a better deal.