This product is too long to sell online. If a local store does not stock it, they can special order it. Some corrugated panels do have extended lead times due to Palram manufacturing COVID protection materials.
Use EPDM washered fasteners only. NEVER use nails. Predrill all fastener holes with a 1/4" drill bit to accommodate for the thermal movement of the panel. Failure to accommodate thermal movement will cause buckling of the sheet. Attach fasteners on the crown of every other rib in the horizontal direction. In high wind areas, fasten on the crown of every rib. Use 2" fasteners for all roof applications. DO NOT Overtighten Fasteners causing the rubber washer to compress.
The fire rating is Class A and CC1.
This product is a soft plastic material that probably wont take any color, stain or paint. It also melta when in direct sunlight.
You overlap one corrugation side to side. If overlapping length-wise, you would overlap 4-6"
Depend how closely you place the fasten screws and how many inch's you overlaps the panels . I used it for the roofing for a shed, no problems. I was able to overlap each panel 3 to 4 inches and I used screws with attached rubber washers.
It's OPAQUE meaning no light passes through. For greenhouse purpose try polycarbonate versions or simple clear(very brittle in cold weather and not long lasting) . I haven't tried POLY CARBONATE version but assume it is stronger and more durable, LIGHT does pass through (smoke, clear) it.