01
Identify the actual geometry
Provide drawings or templates reviewed by the installer. Clarify dimensions, handed pieces where relevant, thickness range, quantity, and whether shaping occurs at the quarry, supplier, or job site. A photograph without scale may communicate appearance but cannot reliably define the order.
02
Confirm how the pieces fit the schedule
Ask about sample approval, production timing, packaging, and replacement availability. Coordinate these items with the installation sequence so the crew does not reach a detail without suitable material. Keep approved templates and supplier correspondence in the closeout records. The field-slate order and the special-piece order should be traceable to the same roof layout.