A contractor may have a legitimate reason to propose a different coating, but a material substitution should not happen invisibly. Changing the product can change preparation, primer, film thickness, dry time, warranty, compatibility, color/sheen, approval status and maintenance.
Brand Is Not the Specification
“Use Sherwin-Williams” or “use INSECO” still leaves many possible products. A useful proposal identifies the line or exact system. That matters because one manufacturer can sell architectural paint, masonry conditioner, elastomeric wall coating, concrete sealer, urethane, acrylic roof coating and silicone roof coating with very different instructions.
When a Substitution May Be Reasonable
- The specified product is unavailable and the proposed replacement has demonstrably equivalent requirements and performance for the substrate.
- A field condition changes the system—for example, unexpected chalk, high pH, unknown sealer or silicone contamination requires a different primer or preparation.
- The manufacturer updates or replaces a product line.
- The homeowner changes color, sheen, use condition or warranty requirement.
When Substitution Is a Bigger Deal
For specialty systems, the product list may be part of the approval or warranty. Florida Product Approval records, for example, identify specific models/systems and publish limits of use and installation documentation. Replacing one component with an unlisted alternative can therefore be more than a cosmetic brand switch.
Compatibility also matters when recoating silicone, old acrylics, urethanes, epoxies, paver sealers and other films. A different chemistry can require a primer, test patch or complete removal. “Better product” is not a sufficient compatibility test.
A Simple Contract Rule
Write the specified products into the proposal and require homeowner approval for material substitutions that change the named system. If a substitution is proposed, ask for the new technical data sheet and compare substrate, preparation, spreading rate, film thickness, cure time, limitations, warranty and approval documentation.