How heavy are Solar Panels when mounted on the roof?Do the impact the roof structure or roof warranties?

Panels weigh around 18kg per panel, which is spread over approx. 1.5m2, so they weigh a lot less than a person walking over the roof.

PowerSmart solar systems do not void any roof warranties. When installing solar panels PowerSmart is very aware of not damaging the roof. We limit roof penetrations and have completed whole commercial installations in the past reusing existing roofing screw holes.