1. First Class Bricks
These bricks are well brunt having smooth and ecen surface with perfect rectangualr shape and uniform reddish colour. These bricks should not absorb water more than 20% of its own dry weight after 24 hours of immersion in water. It should have a minimum crushing strength of 10.5 MN/m^2
2) Second Class Bricks
These brikcs are slightly over brunt having rough surface and nor perfectly rectangular in shape. These bricks should nor absorb water more than 22 percent of its own dry weight after 24 hours immersion in water.It should have a minimum crushing strength of 7.5 MN/m^2
3) Third Class Bricks
These bricks are not brunt in the kiln and hence these are soft and can be easily broken. These bricks should not absorb water more than 25 percent of its own dry weight after 24 hours immersion in water.
4) Jhama / poor Bricks
These bricks are over brunt with irregular shape. These bricks are dark and bluish colour.
The standard size of the bricks are 19 cm * 9 cm * 4 cm
The specific gravity of brick is about 2 .
the number of bricks required for 1 cubic meter of brick masonry is 562.