Estimates & payments

What is a supplemental claim, and how do I file one?

Q: What is a supplemental claim, and how do I file one?

A supplemental claim (supplement) requests additional payment for costs discovered after the initial estimate — hidden damage found during repairs, code-required upgrades, or price differences. To file one: document the additional damage with photos, have your contractor write a line-item supplement with justification, submit it in writing to the adjuster, and follow up until it's approved before the work is completed where possible.

The short answer: a supplemental claim — a "supplement" — is how you get paid for costs discovered after the first estimate: hidden damage found when walls come open, code-required upgrades, materials that cost more than the software priced. If it wasn't in the scope, it won't be paid unless you supplement it. This is where a large share of missing claim money lives, and most homeowners have never heard of it.

Why supplements exist

The adjuster's first estimate is written from a single visit, before any demolition. But real repairs reveal real surprises: rotted framing behind the drywall, wiring that no longer meets code, flooring that can't be matched and must be replaced as a continuous run. None of that was visible on day one — so none of it is in the first check. The supplement is the mechanism for getting it covered. It's a normal part of the process, not a confrontation.

What qualifies

Hidden damage discovered during repairs — what the walls were hiding.
Code upgrades required by your local building department to complete the repair legally (permits, electrical, plumbing).
Price differences — materials or labor that genuinely cost more than the estimating software allowed.
Scope corrections — line items the first estimate missed entirely.

What doesn't qualify: upgrades you simply want (nicer tile, a better fixture than what was damaged) — the policy owes you restoration to pre-loss condition, not a remodel.

How to file one

Stop and document when additional damage is found. Photos, measurements, and a written description before anything gets covered back up.
Have your contractor write the supplement as a line-item document: each additional item, its cost, and why it's necessary (code section, photo reference, manufacturer spec). A supplement that explains itself gets approved faster than one that just lists numbers.
Submit it in writing to the adjuster — email with the supplement and photos attached. Ask for written approval.
Get approval before the work is done whenever possible. It's far easier to get a supplement approved for work the adjuster can still inspect than for work that's already behind new drywall.
Follow up on a schedule. Supplements sit in queues. A polite weekly check-in keeps yours moving.

This is where good contractors earn their keep Contractors who document supplements thoroughly — photos, code citations, clear line items — get them approved. If your contractor shrugs at the idea of writing a supplement, that's useful information about your contractor.

Don't pay out of pocket for covered extras without asking If your contractor discovers additional damage mid-job, pause and supplement first. Paying for it yourself and asking for reimbursement later is a much harder fight than getting approval up front.

Informational only — not legal or insurance advice.

Insurance rules vary by state and by policy. Check your own policy documents and your state's insurance department, or talk to a licensed professional, before acting on a claim.

What a supplement can cover

Common supplemental claim items
Found after the first estimate	Why it was missed
Hidden water damage behind walls	Not visible until demolition
Code upgrades required by permit	Adjuster priced to old code
Price increases since the estimate	Material/labor costs moved
Additional rooms affected	Damage spread or was overlooked