Depending on the usage of Steel Buildings, the Lighting requirement varies between 3% to 7% of the total roof area of Pre-Engineered Metal Building. We use high-quality Individual Polycarbonate Sheets or Strips. For the base of Turbo Vents, we use Polycarbonate sheets that provide extra daylight. Unlike most thermoplastics, polycarbonate can undergo large plastic deformations without cracking or breaking.