The glazing we use is multi-layer polycarbonate. It comes in several configurations, and the version you would need will depend on your specific site and other design details such as volume-to-surface ratio, insulation, radiant barriers, angles of reflection and refraction, and more. Similar products are available in vinyl, which lasts longer but is more expensive. Other types of glazing will work, including glass. The material is not as important as its performance under your specific conditions.