The situation with steel decks

Steel roof deck design can affect roof system selection and design

Steel roof decks commonly are encountered in low-slope roofing projects. According to NRCA's 2015-16 Annual Market Survey, steel roof decks are used in a majority of new construction building projects. Also, NRCA's market survey shows steel roof decks are in place on about half of all existing building reroofing projects.

Although steel roof decks have enjoyed widespread use and acceptance in the U.S. construction industry for years, the methods used to design steel roof decks to resist wind uplift have evolved and recently changed. Some changes may affect and limit specific roof system designs.

Typically, a building's steel roof deck designer—most commonly the building's structural engineer—will have little to no knowledge of the specific roof system type that will be used on the building. For new construction projects, the specific roof system type typically is selected and specified by an architect or roof consultant and not the roof deck designer.

For reroofing projects, the original designers of steel roof decks most often are not involved nor are structural engineers. During reroofing projects, roof system designers commonly assume steel roof decks were designed properly, are capable of resisting design wind-uplift loads and can transfer the loads to a building's underlying structural system.