Commercial Steel Roll Up Greenhouse Door 3400 is a greenhouse or commercial building door that is made of durable, long-lasting materials. Most parts come pre-assembled, ensuring that installation is quick and easy. This door is ideal for greenhouses, retail applications, commercial and industrial properties, and warehouses in high wind areas. • Designed to meet stringent building codes in coastal regions • Utilizes a 12” drum wheel • The maximum opening size of 20’ wide x 14’ high (280 sq.ft.) • Push-up, hand chain, and electric operations • PSF Ratings: • +35 PSF and -41 PSF for opening widths through 12’ • +35 PSF and -38 PSF for opening widths over 12’ through 16