11 Characteristics of First Class Bricks
As the name suggests, first-class bricks are the most superior bricks in the brick family in terms of quality. They are uniform in size, shape, and colour. First-class bricks are also stronger and more durable than other types of bricks. They are also less inclined to crack or break and have a longer lifespan than other bricks. Due to their superior quality, and weather-resistant properties, they are mostly preferred for use in all types of load-bearing walls, and external walls.
Following are the 11 properties/characteristics of a first-class brick:
1. First-class bricks are table moulded and they are burnt in Kilns.
2. These are well-burnt in kilns.
3. The surface of the first-class brick should be smooth and rectangular.
4. The edges of the brick are perpendicular(Make an angle 90°) to the adjoining edges.
5. They are regular in shape and size with sharp edges and corners.
6. They shall be of uniform deep red colour.
7. They should be free from any cracks.
8. They should be free from chips, efflorescence, flaws, and lumps of any kind.
9. Dry first-class bricks should not absorb water more than 16% of their own weight when immersed in water for 24 hours.
10. They emit a clear ringing sound when two bricks are struck each other.
11. The average compressive strength of the first-class bricks should not be less than 100kg/sq.cm and not more than 125 kg/sq.cm.
Note: First class bricks are recommended for permanent and superior work.
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