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At present, SDI has eighteen deck producing members whose designated representatives serve on the Board of Directors. Additionally, there are ten associate members whose products are used in the manufacture of or construction with steel deck. Although this latter category cannot vote on issues coming before the Board, associate members are encouraged to sit on committees and provide input commensurate with their particular industry’s interests when SDI Recommendations are either prepared for eventual publication or revised.


The SDI maintains relationships with other national agencies which publish Standards, Specifications or Recommendations governing design application of steel materials used in construction. Either through suitable facilities available at members’ plants, or by contract with independent research corporations, SDI carries on continuing test programs. A twofold purpose is generally the reason for this activity:


  • To prove that an existing Standard should be amended or revised because it is discriminatory or outdated, and
  • To develop supporting data which can be used as proof of computed values

Through substantial media advertising and publication of technical brochures, SDI producers and associates enjoy continuous exposure to professional and trades people.


  • Replaced gage with design thickness as the unit of measure in references to material thickness;
  • Established manufacturing tolerances;
  • Developed site storage and erection recommendations;
  • Standardized accessories-sump pans, ridge and valley plates, and cant strips;
  • Developed specifications for Composite Steel Floor Deck, Non-Composite Steel Form Deck, and Steel Roof Deck;
  • Defined standard roof deck sections and issued standard load tables for narrow, intermediate, wide rib and deep rib decks.
  • Developed design procedures and standard load tables for composite deck.


Independent tests are the best guide to product performance and reliability, a philosophy to which Steel Deck Institute members subscribe. Their support for an ongoing program is indicated by the number and scope of tests already performed and by their policy of sponsoring new tests when new products or applications are introduced by the industry.

Following are completed roof deck tests for which published results are available:

  • U.L. Fire Ratings: two-hour steel deck assembly; acoustical ceiling with wide joist spacing; steel roof assembly with directly applied insulation;
  • National Bureau of Standards fire tests on various steel roof deck constructions;
  • Steel Deck Diaphragms.

SDI manufacturers can furnish fire ratings, load test results, and other performance test reports for their own products.