Polycarbonate Roofing sheet shed contractors In padappai Sheet Type: Ask for Multiwall if you need heat insulation (ideal for greenhouses/patios) or Solid/Compact sheets if you want a glass-like clear look with high impact resistance. Structure Material: Ensure the frame is powder-coated or galvanized to prevent rust, especially if you live in a coastal or high-humidity area. UV Protection: Verify that the sheets are UV-coated. Without this, polycarbonate will yellow and become brittle within 2–3 years of sun exposure. Waterproofing: Confirm they use high-quality EPDM gaskets and silicone sealants at the joints to prevent leaks during monsoons.