Unit Weight of Building Materials

What is Unit Weight?

Weight per unit volume is known as the unit weight of the material.

The unit weight of building material is very important from the design perspective of a building. A structural design engineer should have complete knowledge of the unit weight of materials. The unit weight of different building materials is given in the below table.

Table No 1:

PCC (Plain Cement Concrete)	24 KN/m3
RCC (Reinforced Cement Concrete)	25KN/m3
Portland Cement	14KN/m3
Cement Mortar	20KN/m3
Water	10KN/m3
Dry Sand	16KN/m3
River Sand	18.4KN/m3
Wet sand	11KN/m3 to 20KN/m3
Bricks	16 to 19.2 KN/m3
Bitumen	10.4KN/m3
Brick Masonry	19.2KN/m3
Cement plaster	20KN/m3
Lime plaster	17KN/m3
Broken Bricks	14.2KN/m3
Dry, Loose Earth	12KN/m3
Dry, Loose Sand	14.4-17KN/m3
Silt	21KN/m3
Igneous rock	27KN/m3
Sedimentary rock	26KN/m3
Metamorphic rock	27KN/m3

Table No 2:

Mud	16KN/m3
Granite	24.5KN/m3
Marble	26.5KN/m3
Aggregate	17.5KN/m3
Lime concrete	19KN/m3
Clay (Dry)	16KN/m3
Clay (Damp)	17.6KN/m3
Gravel	20KN/m3
Ballast	17.2KN/m3
Chalk	22.4KN/m3
Willow Timber	420Kg/m3
Teak Timber	650Kg/m3
Sal Timber	10KN/m3
Asbestos Cement Sheet	12 to 15.6Kg/m3
Glass	24-27.2KN/m3
Charcoal	530Kg/m3
Tin	72KN/m3
Nickel	8.9KN/m3
Clinker	750Kg/m3
Copper	89KN/m3

Table No 3:

Stainless Steel	74.5KN/m3
Aluminum	27KN/m3
Ice	910Kg/m3
Slag	15KN/m3

How to Calculate the Unit Weight of Materials

You can calculate the unit weight of any material but you have to know the density of that material.

Formula of density = kg/m3

Now we have to eliminate m3 from the denominator to get the specific weight or unit weight.

As we know volume is measured in m3, so we can multiply density by volume.

Unit weight = Density*volume

Unit weight = (kg/m3) * m3

This is the simplest method to calculate the unit weight of building materials.