Property Restoration Supplement Letters: A Complete Guide for Contractors

The Restoration Supplement Challenge

Property restoration contractors — those who handle water damage, fire damage, smoke damage, and mold remediation — face the same fundamental challenge as auto body shops: the full scope of damage often isn't apparent until the work begins. A water damage claim that looks like a simple drywall replacement often reveals structural damage, mold, and electrical issues once the walls are opened.

The difference is that restoration contractors often have less experience writing supplement letters than auto body shops, and the documentation requirements are different. This guide covers the specific strategies for restoration supplement letters.

Types of Restoration Supplements

The most common reasons for restoration supplement requests include:

• Hidden structural damage: Damage to framing, subfloor, or structural members not visible during initial inspection
• Mold discovered during remediation: Mold behind walls, under flooring, or in structural cavities
• Asbestos or lead paint: Hazardous materials discovered during demolition that require specialized handling
• Additional affected areas: Water or smoke damage that spread further than initially apparent
• Code upgrades: Required code upgrades triggered by the extent of the repair (electrical, plumbing, HVAC)
• Contents damage: Personal property damage discovered during the restoration process

The Restoration Supplement Letter Structure

A restoration supplement letter follows the same basic structure as an auto body supplement letter, with some important differences:

1. Reference the Original Claim and Scope of Work

Start by referencing the original claim number, the date of loss, the type of loss (water, fire, etc.), and the original approved scope of work. This establishes the baseline against which the supplement is being requested.

2. Describe the Additional Damage Found

Describe the additional damage in technical terms. For water damage, include moisture readings (using a moisture meter) showing the extent of saturation. For mold, include air quality test results or visual documentation. For structural damage, include measurements and photos.

3. Cite the Industry Standard

Restoration supplements are strengthened by citations from IICRC (Institute of Inspection, Cleaning and Restoration Certification) standards. The IICRC S500 (water damage), S520 (mold remediation), and S770 (fire and smoke damage) standards are widely recognized by insurance adjusters and provide the same authority as OEM procedures in auto body supplements.

4. Document the Code Requirements

If code upgrades are required, include a copy of the applicable building code section and a statement from the local building department (if available) confirming the requirement. Code upgrades are often disputed by adjusters but are legally required and must be included in the scope of work.

Xactimate Line Items for Restoration Supplements

Most property restoration supplements are written using Xactimate, the industry-standard estimating software for restoration claims. When writing a restoration supplement, use the correct Xactimate line item codes and include the appropriate modifiers. Incorrect line item codes are a common reason for supplement denials.