Work out live load instantly with clear inputs, formula shown and shareable results.
Live load intensity comes from the occupancy schedule: about 2 kPa for residential, 3 for offices, 4 for retail and 5 for assembly. Where a member supports a large influence area, codes permit a reduction because full loading everywhere at once is improbable, using a factor of 0.25 + 4.57 / sqrt(influence area) with a floor of 0.4.
Reduction factor
R = 0.25 + 4.57 / sqrt(influence area m²), not less than 0.40
Reduced load
Reduced kPa = tabulated live load x R
Preliminary estimate only. Live load values and permissible reductions must be taken from the loading code adopted locally.
R = 0.25 + 4.57 / sqrt(influence area m²), not less than 0.40. Live load intensity comes from the occupancy schedule: about 2 kPa for residential, 3 for offices, 4 for retail and 5 for assembly.
No. It applies to beams, columns and foundations with large influence areas. The slab itself must carry the full tabulated intensity locally.
This calculator takes 3 inputs: Occupancy type, Tributary area, Floors supported. The pre-filled defaults are a realistic worked example — replace them with your own site or project figures.