Building Class

Every level in the Job Tree may be assigned a Building Class, either Residential or Commercial.

Certain member types within a level will be impacted by the Commercial setting:

  • Floor Joists, Floor Flush Beams: A floor concentrated live load is applied per IBC; section 1607.4 and 2010 NBC of Canada; Division B, section 4.1.5.9. Member analysis is limited to light commercial floor assemblies (office, hospitals, libraries, stores, factories, manufacturing). Floor systems which support vehicles are not considered. For Canada, System Vibration Control calculations are not performed on Floor Joists.
  • All bending member types (Canada only): Snow loads are automatically reduced for deflection calculations. Is = 0.9 for the serviceability limit state even though the Importance Category for the structure is Normal. This approach is inferred by the 2010 NBC of Canada, Division B, Table 4.1.6.2.

When there is a Concentrated Live Load requirement on a commercial floor member, ForteWEB software offers the ability to choose how other floor live loads are to be applied in relation to the Concentrated Live Load check.

The combine checkbox is used to determine whether the floor live load should to be combined with the concentrated live load as the load moves along the member length. It is up to the user to determine if the existing floor live loads based on occupancy or partition loads, should be combined with the concentrated live load.

When the Combine Load box is: The floor live load above the Combine Load box is: Software initially defaults to this setting for:

Checked

Combine with the Concentrated Live Load check
  1. Support reactions that are linked and transferred from other ForteWEB members in the same job.
  2. Loads imported from Javelin that do not originate directly from the floor decking.

Unchecked

Applied independent of the Concentrated Live Load check

All other conditions.

The ability to decide whether or not to combine certain floor live loads with the Concentrated Live Load check allows the user to interpret the intent of applicable building code requirements for commercial floors. Weyerhaeuser® engineering generally adheres to the convention whereby uniform floor live loads from the same floor level as the member itself need not be combined with the Concentrated Live Load check.