01
Define the material precisely
Identify source, product, grade or classification, nominal thickness, dimensions, finish, weathering characteristics, test documentation and acceptable variation. State requirements for samples, delivery identification, storage and substitutions.
02
Coordinate the complete assembly
Draw and specify deck, underlayment zones, headlap, exposure, starter courses, fasteners, valleys, walls, penetrations, hips, ridges, snow retention and ventilation. Details should reflect the selected slate rather than a generic shingle profile.
03
Qualify workmanship and verification
Require relevant natural-slate experience, a representative mockup, preinstallation coordination and documentation of concealed details. Define observation milestones before underlayment, flashings or fasteners are hidden.