How to calculate dead load and live load?

Dead loads and Live loads are act on the slab may vary for Floor slab and Roof slab. Some assumptions have to be made to understand the calculations of Dead and Live loads acting on the slab.

Let us assume that the type of occupancy of the building is Office Building,

The shorter span of the Slab = 4m (Size of Slab = 5m x 4m)

Thickness of Slab = 130 mm

Weight Density of concrete = 25 kN/cu.m

Dead Loads:

According to IS 875 Part-I 1978. Dead loads shall be calculated as:

Floor Finish = 1.00 kN/sq.m

Light Partition = 1.00 kN/sq.m

Weight due to weathering and Pressed tiles = 2.50 kN/sq.m

Live Loads:

According to IS 875 Part-II 1978. the Live loads shall be calculated as:

Live load on Floors (Office building) = 3.00 kN/m2

Live load on Roofs (Office building) = 1.50 kN/m2

Floor Loads:
a). Dead Load:
Self-weight of the slab = 0.12 x 25	3.00 kN/m2
Floor Finish	1.00 kN/m2
Light Partition	1.00 kN/m2
b). Live Load on Floors	3.00 kN/m2
Hence, Total Floor load on the Slab	8.00 kN/m2
Roof Loads:
a). Dead Load:
Self-weight of the slab = 0.12 x 25	3.00 kN/m2
Weight due to weathering course and Pressed tiles	2.50 kN/m2
b). Live Load on Roofs	1.50 kN/m2
Hence, Total Roof load on the Slab	7.00 kN/m2