ASCE 7-05 Code Information
The ASCE 7 Standard Minimum Design Loads for Buildings and Other Structures is the document the International Building Code (IBC) relies on for its structural and nonstructural requirements. ASCE 7-05, was the standard referenced in the 2006 and 2009 IBC’s, but has now been substituted by ASCE 7-10 in the 2012 IBC. Per the code updates, there are some changes in the nonstructural requirements for commercial building that may affect your project.
The differences below are directly from ASCE 7 and pertain to structures in Seismic Design Categories C, D, E and F. They do not account for State or Local code amendments (if any).
- The single most significant change is the addition of an Omega over-strength factor requirement for anchorages to concrete. The over-strength factor results in a significant reduction in anchorage allowable design capacity to the extent that allowable anchor load may govern maximum allowable brace spacing. Simply put, this reduced anchorage capacity greatly increases the likelihood that anchorage capacity may govern the maximum allowable brace spacing. Reductions in brace spacing vs. that under ASCE 7-05 are likely particularly in areas with high horizontal ground accelerations.
- ELECTRICAL SYSTEMS
- ASCE 7-05: Brace all conduit greater than 2-1/2” trade size and all trapeze supported raceways supporting loads greater than 10 lbs/lf.
- ASCE 7-10: Brace all conduit equal to or greater than 2-1/2” trade size and all trapeze supported raceways supporting loads equal to or greater than 10 lbs/lf.
- PLUMBING and MECHANICAL PIPING
- ASCE 7-05: Brace all trapeze assemblies designed to support loads greater than 10 lbs/lf.
- ASCE 7-10: Brace all trapeze assemblies designed to support loads greater than or equal to 10 lbs/lf.
- HVAC DUCT
- ASCE 7-05: Brace all suspended ductwork greater than or equal to 6 Sq Ft. cross-sectional area or weighing greater than 5 lbs/lf.
- ASCE 7-10: Brace all suspended ductwork greater than or equal to 6 Sq Ft. cross-sectional area or weighing greater than 17 lbs/lf.
- Brace all duct designed to carry or convey toxic, highly toxic or flammable gases or used for smoke control.