01
Check the complete change
Send the installer the proposed material dimensions, thickness range, relevant documentation, and any system differences. Have the designer review matters within their responsibility. Do this before the supplier ships, while there is still an opportunity to resolve incompatibilities without material sitting on site.
02
Update the common reference
If the substitution is accepted, revise the order, quantity schedule, and relevant details together. Identify superseded selections so the crew does not mix old and new instructions. Keep the approval record with the delivered product identification. A substitution is complete when the project participants are working from the same accepted information, not merely when one person agrees to a different product name.