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Steel Door Institute, Steel Door, Fire Rated Doors, Hollow Metal Door

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.

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, an extensive set of 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. Each member is actively involved in committees that develop codes, fire tests, and more.

When you specify SDI member manufacturers you can be assured you will receive a product that is well-constructed, tested, and evaluated to meet your specifications.


When to Specify Knock Down vs. Welded Frames

Steel Frame Door

Design professionals are constantly deciding which type of frame is best-suited for their project: knock down or welded.

To help you decide, we’ve put together a primer that covers the most popular types of frame constructions, along with the pros and cons of each.

KD Versus Welded Frames >>



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