An anchor rod support comprises a support having a floor and legs extending downwardly from the floor with openings between the legs; and the support including threads for attaching thereto an anchor rod.

An anchor holder for concrete decks comprises a body for being inserted into an opening in a metal deck, the body including an outside vertical wall and an opening for receiving an anchor. The body includes arms normally biased extending outwardly from the vertical wall, the arms being collapsible toward the body when the body is inserted into the opening in the metal deck and expanding outwardly after passing the opening to be disposed below the metal deck. A support is attached to the body, the support to engage a top surface of the metal deck to apply an upward force on the body and keep the collapsible arms engaged against an underside of the metal deck when the body is attached to the metal deck.

A concrete anchor assembly includes a housing having a top opening; the housing including a bottom wall with a bottom opening; the bottom wall including a ramp surface extending upwardly and away from the bottom opening; a split nut disposed on the bottom wall and over the bottom opening; and a spring biased to force the split nut toward a bottom of the ramp surface.