Dimensions Width: 9', 12', or 18' Length: 12', 18', 24', 30', or 36' Height: 9' 1-7/8", 10' 5/16", or 11' 8-15/16" Sidewall 5' 6" Frame Steel Color Silver Covering 6mm polycarbonate twin-wall covering Door(s) (1) 3' x 6'-8" storm door Roof Vents 0 End Vents 0 Side Vents 0 Base n/a Foundation Options - Concrete Piers or Slab Warranty Covering - 10 years Manual Included This is the perfect greenhouse for starting a greenhouse business. A commercial quality greenhouse at a price that will not break