UBC 1997 live load reduction is specified in code section 1607.5. Live load effects on members with tributary areas of 150 square feet or less are not modified by live load reduction.

Equation (7-2) [R = 23.1 (1 + D/L)] is not considered in live load reduction calculations. This value needs to be calculated and set by the user in the maximum reduction property.

UBC 1997 requires that storage loads in excess of 100 psf shall not be reduced, except that live loads on columns may be reduced up to 20%. These loads must be drawn on a Live (Storage) loading to be considered appropriately.

UBC 1997 requires that other live loads in excess of 100 psf or in places of public assembly occupancies cannot be reduced. These loads must be drawn on a Live (Unreducible) loading to be considered appropriately.

UBC 1997 can be used as IBC 2003 alternate live load reduction in accordance with IBC section 1607.9.2. Because minimum parking loads in UBC 1997 are higher than IBC 2003 minimum parking loads, it may not be appropriate to apply UBC 1997 parking garage reduction provisions to IBC 2003 loadings. For this reason, parking garage loads should be drawn on a Live (Storage) loading and thus will get a maximum 20% reduction on columns and no live load reduction on other members.