Live load reduction factors

Calculate the live load reduction factor for different use and occupancies according to ASCE 7 or NBCC

Tributary Area:

=
ASCE 7 Equation 4.7-1:

Notes: LLRF shall not be less than 0.50 for members supporting one floor, and 0.40 for members supporting two or more floors.

Live loads which exceed 100psf (4.8kPa) shall not be reduced (cl. 4.7.3), except that members supporting two or more floors may be reduced by a maximum of 20%.

National Building Code of Canada (NBCC)

NBCC Equation 4.1.5.8.(2):

Notes: This equation is for assembly areas designed for a LL of 100psf (4.8kPa) or more, as well as storage, manufacturing, retail, garages, and footbridges.

Assembly areas designed for less than 100psf (4.8kPa) and roofs designed for the minimum LL of 20psf (1kPa) shall not be reduced.

NBCC Equation 4.1.5.8.(3):

Notes: This equation is for any use or occupancy other than those listed in 4.1.5.8.(2).

Assembly areas designed for less than 100psf (4.8kPa) and roofs designed for the minimum LL of 20psf (1kPa) shall not be reduced.