Greenhouse covering materials determine light transmission, insulation, and durability. Polyethylene film offers low cost with 80-90% light transmission. Polycarbonate sheets provide excellent insulation with impact resistance. Glass offers the highest light transmission at 90-95% with long service life. Film must be replaced every 2-4 years while polycarbonate lasts 10-15 years. UV inhibitors prevent material degradation from sunlight exposure. Anti-condensation coatings reduce droplet formation. Light-diffusing materials scatter sunlight for more uniform crop illumination. Double-layer coverings with air gaps improve insulation significantly.