01
Compare patterns at building scale
A sample of one piece cannot show the effect of repeated courses across a roof plane. Ask for drawings or photographs that make the difference in module clear. Consider window sizes, dormer spacing, and the roof's overall proportions alongside the proposed slate dimensions.
02
Recheck the technical and quantity consequences
Changing size also changes the installation layout and potentially the required piece count. Have the installer review the proposed dimensions within the specified system, then update the quantity schedule. Keep the accepted size in the material specification rather than allowing an appearance discussion to become an undocumented site substitution. A successful choice coordinates proportion, availability, and the complete roof design.