What a Roof Replacement Estimate Should Cover

Why a roof estimate needs its own checklist

Our general guide to reading a contractor's quote covers scope, allowances, exclusions, change orders, and payment schedules — and every one of those still applies to a roof. This guide adds what is specific to roofing: the deck underneath is invisible until the old material is off, the underlayment and flashing choices are real performance decisions rather than boilerplate, local code sets a minimum for ice protection in cold climates, and a storm claim can put a second, insurer-written estimate into the picture that reads nothing like your contractor's.

The roofing-specific fields

Ice barrier requirement per the International Residential Code, section R905.1.2 (2021 edition) — check whether your jurisdiction has adopted this edition or amended it, since code adoption varies by state and locality.

Two more code checks a complete estimate should pass

Attic ventilation. The International Residential Code sets a minimum net free ventilating area for the attic or roof space, not just a recommendation: Section R806.2 requires 1/150 of the vented floor area as a baseline, reduced to 1/300 only when specific conditions are met — for example, when 40–50% of the required ventilation is placed in the upper portion of the attic (within 3 feet of the ridge) and the rest low, giving a balanced intake-and-exhaust path. This is not decorative: inadequate ventilation traps heat and moisture under the new roof, which shortens shingle life and can void a manufacturer's warranty outright. If your estimate adds, removes, or changes vents, it should say how the new count meets this ratio for your attic's actual square footage — not just that “ventilation is included.”

Tear-off vs. overlay. The IRC does not leave “can we roof over the old one” to preference. A new layer cannot be installed over an existing roof where the existing roof already has two or more layers of any roof covering, where the existing covering is water-soaked or too deteriorated to serve as a base, or where the existing covering is wood shake, slate, clay, cement, or asbestos-cement tile — any of those conditions requires a full tear-off before new roofing goes on. That is the code basis behind the “tear-off layer count” line in the table above: an estimate proposing to roof over an existing layer should be able to say why that is permitted on your specific roof, not simply omit the question.

A storm-claim estimate is not the same document

If the roof is being replaced because of hail or wind damage, your insurer will typically generate its own independent estimate of the covered damage, priced by the insurer's own process — not your specific contractor's costs or margin. We are not going to describe that process in more detail than that; none of this guide's sources document how any particular insurer or claims system prices a roof, and naming one would be guessing. That estimate and your contractor's estimate are answering different questions, and it is normal for them to disagree. Reconciling the two — through a supplement request to the insurer, backed by your contractor's documented scope — is the homeowner's job, not something either side does automatically.

Storms also draw “storm chasers” — crews from outside the area who show up wherever a storm just hit and pitch roofing work homeowner to homeowner, unsolicited. The National Insurance Crime Bureau, partnering with the Insurance Institute for Business & Home Safety, has documented this pattern; treat an unsolicited door-knock roofing pitch the same way you would treat any other unsolicited sales call, and get your own contractor's estimate regardless of who knocked first.

Permit, disposal, and why “warranty” means two different things

Permit and disposal are administrative line items, not afterthoughts, and leaving either implicit is how a homeowner ends up with a surprise charge partway through the job. Most jurisdictions require a permit for a full re-roof, and it should be the licensed contractor pulling it — an estimate that is silent on who is responsible, or that suggests skipping the permit to save time or money, is a red flag on its own, separate from price. Disposal works the same way: tear-off produces a full dumpster or truckload of old shingles and underlayment, and the estimate should say who hauls it and where the cost sits, rather than leaving it to be billed once the job is already underway and you have no leverage to negotiate.

The two warranties named in the table above are not a formality — they cover different failure modes and different parties. The manufacturer's material warranty covers defects in the shingles or underlayment themselves — cracking, granule loss, premature failure of the product as manufactured — and is backed by the manufacturer regardless of which contractor installed it. The installing contractor's workmanship warranty covers their own labor — a leak from a flashing detail done wrong, or nailing that does not meet the shingle manufacturer's pattern, both of which are installation errors a material warranty does not cover and will not pay for. A roof failure traced to bad installation on a roof with only a material warranty can leave you with no coverage at all for the actual cause, which is why an estimate naming only one of the two is telling you about half your protection, not all of it.

Once the estimate is complete, check the price separately

Everything above is about whether the document describes your roof correctly. Once it does, that is a separate question from whether the number at the bottom is reasonable for your material, your roof area, and your market — that comparison is what our calculators are for.

• Roof replacement cost calculator — priced by material and roof size
• Roof cost per square foot calculator — for checking a quoted rate directly

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