Classification Of Bricks | Types Of Bricks In Civil Engineering

What is a brick?

Brick is a man-made building material that is usually made of clay. The clay is first molded in a rectangular box and after that put for dry and at the end burning the rectangular blocks and finally, we have different types of bricks.

As we know that the bricks are the most important building material in the construction of different types of buildings. So for our dream house or building, we should choose brick carefully.

Classification of bricks

Types of bricks depend on various factors like what is the strength of bricks, types of finishing of bricks, the field practice, etc.

Here is the classification of bricks in civil engineering that is used in the construction of buildings or houses.

1. First Class Bricks
2. Second class Bricks
3. Third Class Bricks
4. Fourth Class Bricks
5. Hand-Made
6. Machine Made
7. Engineering Bricks
8. Facing Bricks
9. Common Bricks

First Class Bricks

First-class bricks are deep red, cherry, or copper color and it is thoroughly burnt in kilns.

First-class bricks should be free from cracks, stones, and when two first-class bricks are struck each other there should be metallic sound produce.

Water absorption of the first-class brick should be 12-15% when put into water for 24 hours and for first-class bricks there should be no impression left when someone scratches by their fingernail.

The texture in First class bricks should have uniform and brick should have square corners.

First-class brick should have straight edges and be in a rectangular shape and the crushing strength of the first-class brick should not be less than 10 N/mm^2.

First-class bricks are used for superior works due to their strong strength, durability, and pleasant appearance.

Second Class Bricks

Second-class bricks are ground molded and thoroughly burnt in kilns and second-class bricks have non-uniform edges.

Water absorption for the second-class bricks should be 16-20% of its dry weight when put into water for 24 hours.

Second-class bricks have somewhat small cracks and small distortions in the shape and the crushing strength for the second-class bricks should not be less than 7N/mm^2.

Second-class bricks are used in the undercoat plaster because second-class bricks are not good quality as first-class bricks.

Third Class Bricks

Third-class bricks are underburnt bricks, ground molded, burnt in clamps, and these bricks are not hard than first and second-class bricks.

Water absorption for the third-class bricks should be 25% of their dry weight when put into water for 24 hours.

When two bricks of third-class bricks are struck each other there should be dull sound produce.

In third-class bricks, there is an impression left when someone scratches by their fingernail, and third-class bricks have more cracks and irregular edges than second-class bricks.

Due to its poor quality like its non-uniform color throughout brick, more water absorption capacity, non-uniform size, the third-class bricks are used in temporary structures.

Fourth Class Bricks

Fourth-class bricks are overburnt, having a dark color, and having irregular shape and size, and are more distorted than third-class bricks.

The fourth class bricks are used in foundation, floors, roads, due to their non-uniform shape and size of a brick.

What is hand-made brick?

The bricks which are made by hand are called hand-made bricks. It is a very slow process of making bricks compared to a machine-made process.

Hand-made bricks are more costly than machine-made bricks.

What is machine-made brick?

The bricks which are made through the machine are called machine-made bricks. It is a very fast process of making bricks compare to the hand-made process.

Machine-made bricks are cost-effective than hand-made bricks.

Machine-made bricks are of three types. The first is pressed brick second is wire-cut bricks and the last one is molded bricks.

What are engineering bricks?

Engineering bricks are table molded and have high compressive strength and it is available in two color red and blue.

Engineering bricks are used in civil engineering for example in the sewage, retaining walls, groundwork, etc.

Engineering bricks are classified as class A and class B engineering bricks depends on their compressive strength and water absorption capacity of the bricks.

Class A engineering bricks

Class A engineering bricks have a water absorption capacity of less than 4.5% and class A engineering bricks have higher compressive strength than class b engineering bricks.

The class A engineering bricks are not more in use than class B engineering bricks.

Class B engineering bricks

Class B engineering bricks have a water absorption capacity of less than 7 % which is higher than the class A engineering bricks.

Class B engineering bricks are more in use and they have lower compressive strength than class A engineering bricks.

What are facing bricks?

The facing bricks are those bricks that are using for external walls of buildings for good appearance.

Facing bricks should be more durable in atmosphere conditions because facing bricks are exposed to the atmosphere.

What are the common bricks?

Common bricks are those bricks that do not require any good appearance and it has very low quality.

Common bricks are used in interior walls.

The manufacturing of common bricks is economical as they do not require any specific appearance.

The compressive strength and resistance of common brick are very low and they vary greatly in strength and durability.

Crushing Strength Of The Bricks

Type of bricks	Crushing strength
First-class brick	should not be less than 10 N/mm^2
Second class brick	should not be less than 7 N/mm^2.
Third class brick	should not be less than 3.5 N/mm^2

Water Absorption Of The Bricks

Type of bricks	Water absorption percentage by weight
First-class brick	12-15%
Second class brick	16-20%
Third class bricks	25%

Frequently Asked Questions

Here is the list of frequently asked questions on the bricks.

That wraps up my analysis of Classification Of Bricks. I hope you found the data interesting and useful. It’s time to hear what you have to say.

Maybe you have any questions, let me know your thoughts in the comments section below.