Rule of thumb
End Supports must support at least as much of the steel deck sheet as the deck is deep. Middle Supports must support at least as much of the deck sheet as twice the depth of the deck. See the tables to the right for roof deck and composite floor deck calculated values.
Meeting the minimum bearing widths will spread out the supporting force, reducing the chance of the sheet buckling at the supports when under load. Meeting the minimum exterior bearing widths also helps to prevent the deck from slipping off the supports during construction and use (proper attachment is also a must!).
How does this impact my sheet lengths?
Add at least twice the depth of the deck to the clear distance between the first and last supports to determine your minimum sheet length. This allows a length equal to the depth of the deck to rest over each of the end supports.
When else would this be useful to consider?
When pouring concrete over a deck that requires shoring, the shoring members must be twice as wide as the depth of the deck.
To ensure that you are selecting the correct gauge and profile for your job, see our previous article on gauge types here If you’d like a human to help you figure all of this stuff out, please call us at 1-800-878-3622