A roofing supplement is a request to revise an insurance estimate for items the original scope missed or underscoped. It is submitted with the carrier estimate, a measurement report, photo documentation, and a line-item justification citing code, manufacturer instruction, or field condition. A desk adjuster reviews it, may request more documentation or a re-inspection, and issues a revised estimate. Clean documentation is what determines how many rounds it takes.
- →A supplement is a documentation exchange, not a negotiation
- →Every line item needs a reason a reviewer can verify without a site visit
- →Measurement report, photos, code citation, and matching line-item format are the four pillars
- →Most stalls are caused by missing documentation, not disagreement
- →Submit before the file closes — reopening a closed file is slower than getting it right
Supplementing has a reputation for being adversarial. It is not, or at least it should not be. A supplement is a request to correct a scope, backed by evidence. Files that approve quickly all look alike: they make it trivially easy for a reviewer to say yes without leaving their desk.
Step 1 — Read the carrier estimate line by line
Before you write anything, inventory what is already there. Print the estimate, or open it side by side with your measured scope. You are looking for three categories: items completely absent, items present at the wrong quantity, and items present at the wrong specification.
| Category | Example | Evidence needed |
|---|---|---|
| Missing item | Drip edge not on the estimate | Photo of the eave condition plus the code or manufacturer requirement |
| Wrong quantity | Estimate shows 28 squares, measured roof is 34.5 | Measurement report with per-facet area and waste calculation |
| Wrong specification | Three-tab priced where architectural was installed | Photo of the existing shingle and the manufacturer identification |
| Missing access or complexity | Steep or high charges absent on a 10/12 roof | Pitch by facet from the measurement report, plus a photo |
| Missing code item | Ice and water where the jurisdiction requires it | The adopted code section for that jurisdiction |
Step 2 — Measure before you write
Quantity disputes are the most common and the most avoidable. If your supplement says the roof is 34.5 squares and provides no source, a reviewer has nothing to check against. If it attaches a report showing each facet's area and pitch, plus ridge, hip, valley, eave, and rake lengths, the reviewer's job becomes arithmetic. A $10 measurement report is cheaper than a second round of correspondence.
State the waste percentage you applied and why — cut-up roof, valley count, starter and ridge coverage. An unexplained waste number reads as padding; an explained one reads as an estimate.
Step 3 — Build the photo record
Photos are the second half of the evidence. The set should let someone who has never been to the property understand the roof. At minimum:
- Four elevations from the ground, with the house identifiable
- Overview shots of each roof plane
- Close-ups of every condition you are claiming, with a reference for scale
- Existing flashing, ventilation, and penetration details
- Decking condition once tear-off starts, if you are claiming replacement
- The shingle identification — a wrapper, a manufacturer stamp, or a clear close-up
- Anything code-related: drip edge, ice barrier line, ventilation net free area
Step 4 — Write the line items in the carrier's language
Submit line items in the same format and nomenclature as the original estimate. A supplement that reads as a parallel document written in a different vocabulary creates work; one that reads as a clean revision of the existing estimate does not. Each item gets a quantity, a unit, and one short paragraph of justification.
Keep the justification factual and specific. "Required by the 2021 IRC as adopted by [jurisdiction], Section R905.2.8.5" is a reason. "Standard practice in this market" is not, unless you can show it. Manufacturer installation instructions carry real weight because failure to follow them voids the warranty on the product the carrier is paying for.
Step 5 — Submit as one complete package
- Cover summary: property, claim number, date of loss, and a one-paragraph statement of what is being requested
- Line-item supplement in the carrier's estimate format
- Justification sheet, item by item
- Measurement report with diagrams
- Photo report, captioned and organized by the conditions claimed
- Code citations for the jurisdiction
- Manufacturer instruction excerpts where relevant
Send it once, complete. Trickling documents in over a week resets someone's review each time and is the most common reason a simple file takes a month.
Step 6 — What happens on the carrier's side
Most supplements land with a desk adjuster or a supplement-handling unit rather than the field adjuster who wrote the original estimate. That reviewer is working from documents only. They will approve items that are clearly supported, question items that are not, and escalate or order a re-inspection when the disagreement is material. Understanding this is the whole game: write for someone with no site knowledge and a queue.
Step 7 — Handling questions and re-inspections
- Answer questions in writing, referencing the document and page that already contains the answer
- If a re-inspection is ordered, be on site with your report, your photos, and your tape
- Do not re-argue approved items — narrow the conversation to what is open
- Ask for the reason in writing when an item is declined; a documented reason is often answerable
- Track every file's open items and follow up on a schedule rather than ad hoc
Why files stall
| Symptom | Usual cause | Fix |
|---|---|---|
| Repeated requests for the same document | Package submitted piecemeal | Resubmit as one indexed package |
| Quantity challenged | No measurement source attached | Attach a per-facet report with diagrams |
| Code item declined | Citation missing or wrong jurisdiction | Cite the adopted code and section for that city or county |
| No response for weeks | File routed to a queue with no owner | Escalate in writing with the claim number and a dated log of contacts |
| Item approved at a lower price | Unit price not supported | Provide the pricing source and the specification being priced |
Timeline expectations
Timelines vary by carrier, state regulation, and catastrophe volume. A clean supplement submitted during a normal period typically moves faster than one submitted in the weeks after a large storm, when every desk in the region is loaded. Plan your production schedule around that reality rather than a best case, and tell the homeowner the truth about it up front.
Make the documentation automatic
Every step above is a documentation step, which means it can be systematized. RoofGenius supplements reads the carrier estimate, compares it against the measured roof and the applicable code items for the jurisdiction, and produces the line items with justification attached. Pair it with a $10 measurement report so the quantities in the write-up have a source, and see a sample package before you submit your next one.