Variations among 1st class, 2nd class and 3rd class bricks

This construction video tutorial briefly explains the variations among first class, second class and third class bricks on the basis of various points like strength, water absorption capacity, raw materials utilized, color, shape etc.

First class bricks

These types of bricks are used for high quality work. The bricks are quite expensive.
To form these types of bricks, good quality materials ranging from clay, silica etc should be utilized.
All the colors like red, brown, cheery etc. should be used uniformly on the first class bricks.
The shapes of first class bricks in regular in edges, face, top, bottom. The shape should be according to standard brick size like 190 mm x 90 mm x 90 mm with adherence to BIS. The corners should be sharp, there should be no pores or cracks on the bricks.
The water absorption capacity for the first class bricks should be under 20%.
The crushing strength of first class bricks should have been 105 Kg/cim2.

Second class bricks

The types of brick are mainly used in constructing internal walls.
The qualities of these bricks are little less as compared to first class bricks.
These are slightly over burned.
The sizes and shapes are quite different as first class bricks. The edges and corner of these bricks are slightly broken.

Water absorption capacity of second class bricks will not surpass 22%.
Compressive or crushing strength of second class bricks should remain at 70 kg/cm2 otherwise the bricks will be cracked.

Third class bricks

Third class bricks are mainly used for temporary structures.
Their sizes and colors are not uniform.

These bricks are over burned and their sizes and shapes change as compared to standard brick sizes.
The colors of these bricks are dark and blackish.
The water absorption capacity of these bricks are 25%.
The crushing strength of these bricks remain at 30 kg/cm2.

To get more information, watch the following video tutorial.