Footballpb32
Structural
Does anyone know the code's stance on fireproofing for lateral braces in Type 1B construction?
Per IBC Table 601, Type 1B requires a 2-hour fire rating fore primary structural frames.
Per IBC 202, primary and secondary frames are defined as follows:
Primary structural frame
[ul]
[li]Columns[/li]
[/ul]
[ul]
[li]Structural members having direct connections to columns, including girders, beams, trusses, and spandrels[/li]
[/ul]
[ul]
[li]Members of the floor and roof construction having direct connections to the columns[/li]
[/ul]
[ul]
[li]Members that are essential to the vertical stability of the primary structural frame under gravity loading[/li]
[/ul]
Secondary structural members
[ul]
[li]Structural members not having direct connections to the columns[/li]
[/ul]
[ul]
[li]Members of the floor and roof construction not having direct connections to the columns[/li]
[/ul]
[ul]
[li]Bracing members that are not designated as part of a primary structural frame[/li]
[/ul]
Per IBC 704.6.1, secondary members require a minimum of 12" of fireproofing. This equates to fireproofing the gusset of a braced frame, but does not imply the brace itself.
Essentially, IBC (IMO) clearly states braces are secondary members. However, you still need to prove the vertical stability of the primary structure under gravity loading (i.e., notional loads). Could this be implied that some of the lateral braces need to be fireproofing for stability and load path? Does anyone have past experience or further research on this topic and how to address fireproofing of Type 1B braces?
Per IBC Table 601, Type 1B requires a 2-hour fire rating fore primary structural frames.
Per IBC 202, primary and secondary frames are defined as follows:
Primary structural frame
[ul]
[li]Columns[/li]
[/ul]
[ul]
[li]Structural members having direct connections to columns, including girders, beams, trusses, and spandrels[/li]
[/ul]
[ul]
[li]Members of the floor and roof construction having direct connections to the columns[/li]
[/ul]
[ul]
[li]Members that are essential to the vertical stability of the primary structural frame under gravity loading[/li]
[/ul]
Secondary structural members
[ul]
[li]Structural members not having direct connections to the columns[/li]
[/ul]
[ul]
[li]Members of the floor and roof construction not having direct connections to the columns[/li]
[/ul]
[ul]
[li]Bracing members that are not designated as part of a primary structural frame[/li]
[/ul]
Per IBC 704.6.1, secondary members require a minimum of 12" of fireproofing. This equates to fireproofing the gusset of a braced frame, but does not imply the brace itself.
Essentially, IBC (IMO) clearly states braces are secondary members. However, you still need to prove the vertical stability of the primary structure under gravity loading (i.e., notional loads). Could this be implied that some of the lateral braces need to be fireproofing for stability and load path? Does anyone have past experience or further research on this topic and how to address fireproofing of Type 1B braces?
