TJI® Joists can be used as ceiling joists. However, one must consider two design aspects that are not present in typical floor or roof joist applications. First, the top flange of the joists require bracing if there is no direct applied sheathing. Secondly, the ceiling joists and end connections will require further consideration if thrust loads from a conventionally framed (rafter) roof system are present. The link below provides additional information and span tables for TJI® Joists in ceiling applications.