Steel sectional doors from SDI are an attractive solution where strength and insulation are required. Integral horizontal reinforcing ribbing and ship lap section seals are only two of the standard features that set them apart from other doors available on the market today. Very rigid, energy saving and long-lasting door system with high strength to weight ratio. Utilizing the latest in polyurethane technology, we've attained the highest 'R' value per inch of all competitive insulation, as well as providing superior foam to steel adhesion and structural integrity. Heavy duty construction assures years of trouble free performance. Download C150 Brochure Hardware Brochure Features Glazing