Bricks Classification According To Indian Standard

Bricks Classification According To Indian Standard – Bricks Classification is done in order to distinguish between bricks so that they can be used accordingly. Indian Standard is followed in this article to classify bricks. Special type of bricks known as “fire bricks” are covered separately at the end.

Burnt Clay Fly Ash Bricks
Burnt Clay Fly Ash Bricks


These are blocks of tampered clay, moulded to suitable shapes and sizes while it is still in a plastic condition, dried in sun and burnt so as to make them strong, hard and durable.

Here is the classification of bricks according to Indian standard. You can Use for Several Projects.

Bricks Classification

As per Indian Standard IS: 1077-1957, the bricks are classified as under

1) First Class Bricks (Class 1)

Class 1 bricks have uniform color, thoroughly burnt and plane rectangular faces with parallel sides and sharp straight right angled edges. They would have fine, compact and uniform texture and emit a clear ringing sound when struck with each other

first class bricks

2) Second Class Bricks (Class 2)

They have uniform color and may be slightly over-burnt. These bricks may be slightly distorted and have round edges. They should have fine, compact, uniform texture and emit a clear ringing sound when struck with each other.

Second Class Bricks

3) Third Class Bricks (Class 3)

They may be over-burnt or under burnt. They may be distorted and have round edges. The defect in uniformity and shape should not be such as to cause difficulty in obtaining uniform courses with their use.

Over Burnt Bricks Example

Water Absorption Of Bricks

The water absorption of bricks after 24 hours immersion in cold water should be as given below considering bricks classification done earlier.

  1. First Class Bricks – 20% by weight
  2. Second Class Bricks – 22% by weight
  3. Third Class Bricks – 25% by weight

Fire Bricks

Fire Bricks are made of “fire clay” or “refractory clay” and burnt at high temperatures in special klins. These bricks are used for the lining of furnances, boilers, combustion chambers and chimneys where high temperature exists. These are generally capable of withstanding high temperatures upto 1700° C.

Fire Brick

The usual composition of fire clay is

  • Slica                                              = 56 to 90%
  • Alumina                                         = 2 to 36%
  • Iron Oxide                                     = 2 to 6%
  • Lime, magnesia, potash and soda   = 8 to 20%

Er. Mukesh Kumar

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Er. Mukesh Kumar is Editor in Chief and Co-Funder at Civil Engineering Website. Mukesh Kumar is a Bachelor in Civil Engineering From MIT. He has work experience in Highway Construction, Bridge Construction, Railway Steel Girder work, Under box culvert construction, Retaining wall construction. He was a lecturer in a Engineering college for more than 6 years.

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