01
Request comparable slate work
Ask for recent projects using similar slate, roof geometry and scope. Repair experience and full-installation experience are related but not identical. Photographs, references and a clear explanation of methods are more useful than broad claims such as ‘we work on all roofs.’
02
Compare written methods
The proposal should identify slate, sizes, thickness, exposure, headlap, fasteners, flashings, underlayment, deck work and how existing material will be handled. For repairs, ask how broken pieces will be removed and replacements secured. Avoid vague allowances that hide critical details.
03
Confirm business basics
Verify licensing where required, insurance, project responsibility, safety, schedule and warranty terms. Confirm who will actually perform the slate work and whether subcontractors are involved. Availability and travel areas can vary by project, especially for specialty contractors.