Spray-foam adhesion: identify the substrate and obtain the required checking method
A bottling-plant liner has an area where installed foam has separated. The team suspects surface residue, but has not established the actual product’s permitted substrate, preparation or required adhesion assessment.
Separate an observed bond concern from its confirmed cause. Obtain the actual product instructions and qualified response before cleaning, priming or respraying a large area. NRC’s example product listing requires the manufacturer’s installation manual and resolution of nonconforming installations; it does not supply a universal hand-pull test. A small patch is useful only when its preparation, assessment method and acceptance meaning are established for the work.
Establish the receiving and checking method
- Identify the actual receiving face. Record the surface material, finish, existing coating and observed condition by location. Confirm that the approved product scope includes that substrate. Give an unknown membrane, coating or residue a specific question rather than naming it as harmless from appearance. Keep the proposed surface with the qualified installer and relevant supplier or design review before expanding the application.
- Obtain a suitable preparation answer. Ask for the actual cleaning, condition and compatibility requirements, including any required primer and its approved use. Coordinate that work with site safety and the receiving surface’s own requirements. Do not select a solvent, abrasive or primer from habit, or assume a vigorous cleaning method is suitable for every coating. Record what the received method changes and who checks completion.
- Agree the actual check and its limits. Establish whether a trial area, field adhesion assessment or another check is required and who is qualified to perform and interpret it. Retain method, preparation, location, timing and acceptance criteria. An informal pull can reveal a concern but does not automatically reproduce a specified test or prove every future bay. Keep any affected protection or control layer subject to its proper repair requirements.
- Record the outcome before extending the work. Connect the actual result to the prepared surface and product, then obtain the responsible response to an unacceptable or uncertain outcome. Retain the accepted method and receiving checks for comparable areas, while reassessing changed surfaces. A successful isolated patch does not erase earlier separated foam; locate that work and retain its assessment and authorized correction separately.
Common mistakes
- Naming the cause from a separated sheet alone.
- Choosing a universal solvent or primer.
- Calling an informal pull the specified adhesion test.
- Using a trial result to erase earlier affected work.
Checklist
The adhesion record should retain
- Located substrate, coating and observed condition.
- Actual permitted product scope and preparation method.
- Required assessment, competence and acceptance basis.
- Trial result, limits and received application decision.
- Separate assessment and correction of affected installed work.
Check your understanding
A prepared patch seems to stick when pulled by hand. Does that approve every liner bay?
