Steel Door Institute
The Steel Door Institute (SDI) was established in 1954 as a voluntary, non-profit business association that develops quality and performance standards for steel doors and frames. Representatives of SDI member companies create and publish these standards, which are made available without charge to architects and other design professionals to ensure quality and consistency of hollow metal doors and frames used in construction. As a complete hollow metal door and frame resource, the SDI website provides all standards, Frequently Asked Questions, and a Gallery of Products. SDI also offers online education for AIA and GBCI credit. SDI members are the only manufacturers certified to meet SDI’s standards for strength, quality and consistency. Manufacturers who hold SDI certification are regularly audited to SDI’s manufacturing, performance, and quality standards. By specifying SDI Certified, design professionals can be confident their products will be true to spec and built to last.