What Is a Roofing Supplement?
A roofing supplement is a formal written request submitted to an insurance carrier asking for additional payment beyond what was included in the original estimate. When a carrier's adjuster writes an Xactimate estimate, they routinely omit line items that are code-required, manufacturer-mandated, or industry-standard.
A supplement corrects that.
Why Carriers Miss Line Items
Insurance adjusters are not roofing contractors. They write estimates quickly, often from aerial imagery and basic damage documentation. The result is an estimate that covers the most obvious work — tear-off and shingle replacement — while missing:
Each of these seems minor. Across a claim, they add up to $3,000–$8,000 or more.
How a Supplement Request Works
1. Document the gaps — Compare the carrier's estimate against what IRC code, state amendments, and manufacturer installation guides require. 2. Build the supplement letter — Write a professional request citing the exact code section, Xactimate line item code, and dollar amount for each missing item. 3. Submit to the carrier — Send the supplement letter with supporting photos, code citations, and any manufacturer installation guides. 4. Negotiate — The carrier's reviewer will respond. Strong code documentation dramatically increases approval rates.
Who Submits Supplements?
How EstimateDelta Makes Supplementing Faster
[EstimateDelta](/pricing) analyzes the carrier's Xactimate PDF, identifies every missing or underpaid line item, and generates a complete supplement letter with code citations in under 2 minutes.
No manual line-item lookup. No hours spent writing letters. Just upload the estimate and get your supplement pack.
[Start your first supplement analysis →](/pricing)