Steel Door Inc.

Steel Door Institute

The #1 resource for commercial steel doors and frames

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.

SDI’s standards are available without charge. Design professionals around the world specify these standards because they are concise and regularly updated with leading industry practices.

Only SDI Certified manufacturers undergo recurring audits to ensure compliance with our standards for strength, quality and consistency. By specifying SDI Certified, you can be assured you will receive a product that is well-constructed, tested, and evaluated to meet your specifications.

In addition to our trusted industry standards, the SDI website has a Door Selector Tool, Drawings and Product Gallery. We also offer online and in-person continuing education for AIA and GBCI credit.

The Best Steel Doors


video on the best steel door options

Steel doors are built to last, and the best steel doors are made from a select group of manufacturers here in the USA. Purchasing SDI Certified doors will ensure you receive a product that can withstand the abuse of everyday life.