When constructing a house or any building, quality standards play a major role in ensuring strength, durability, and safety. In India, the Bureau of Indian Standards (BIS) provides specific IS codes for bricks that guide manufacturers, engineers, and contractors. Knowing the IS code for bricks in building construction helps you choose the right type of brick, test its quality, and follow proper construction practices. Whether you are using burnt clay bricks, fly ash bricks, or hollow bricks, the IS codes act as benchmarks for quality and performance.
Importance of IS Code for Bricks in Construction
IS codes are essential because they set uniform guidelines for size, strength, water absorption, and durability of bricks. They ensure that bricks used in construction meet the minimum standards required for safe and long-lasting structures. Using bricks that comply with IS codes helps to:
- Maintain structural stability
- Avoid cracks and dampness in walls
- Ensure proper load-bearing capacity
- Reduce construction defects
- Improve overall building life
Major IS Codes for Bricks in Building Construction
Several IS codes cover different types of bricks and their applications. Here are the key ones every builder should know:
IS 1077: Specification for Common Burnt Clay Building Bricks
This is the most widely used IS code for bricks in building construction. It defines the requirements for burnt clay bricks used in walls and foundations. Key points include:
- Standard brick size: 190 mm × 90 mm × 90 mm (without mortar)
- Compressive strength: Minimum 3.5 N/mm² for Class 35 bricks
- Water absorption: Should not exceed 20% of brick weight after 24 hours immersion
- Efflorescence: Should not be more than moderate
IS 2180: Specification for Heavy Duty Burnt Clay Building Bricks
This code applies to bricks used in pavements, industrial floors, and heavy-duty construction. These bricks are stronger and more durable than common burnt clay bricks.
IS 12894: Specification for Fly Ash Lime Bricks
Fly ash bricks are eco-friendly and widely used in modern construction. This code specifies requirements such as:
- Compressive strength: 7.5 to 15 N/mm² depending on class
- Water absorption: Should not exceed 20%
- Dimension tolerance: ± 8% of standard size
IS 3952: Specification for Hollow Clay Bricks
This code covers hollow clay bricks, which are lightweight and used for non-load-bearing walls. Key requirements include:
- Compressive strength: 3.5 to 7 N/mm²
- Water absorption: Maximum 15%
- Better thermal insulation compared to solid bricks
IS 3102: Classification of Burnt Clay Solid Bricks
This code provides classification based on compressive strength, shape, and surface finish of solid bricks.
IS 3495 (Parts 1 to 4): Methods of Tests of Burnt Clay Bricks
This code defines testing methods for bricks, covering:
- Part 1: Determination of compressive strength
- Part 2: Determination of water absorption
- Part 3: Determination of efflorescence
- Part 4: Determination of dimension tolerance
IS 2222: Specification for Burnt Clay Perforated Bricks
Perforated bricks are used for lightweight construction and better ventilation. This code specifies their dimensions, strength, and tolerances.
Standard Brick Sizes as per IS Code
According to IS 1077, the modular brick size is 190 mm × 90 mm × 90 mm. With mortar joints, the final size becomes 200 mm × 100 mm × 100 mm. However, non-modular sizes are also allowed depending on local practices.
| Type of Brick | Standard Size (mm) | With Mortar (mm) |
|---|---|---|
| Modular Brick | 190 × 90 × 90 | 200 × 100 × 100 |
| Non-Modular Brick | 230 × 110 × 75 | 240 × 115 × 80 |
Compressive Strength of Bricks as per IS Code
The strength of bricks depends on their class. IS 1077 classifies bricks into different categories based on compressive strength.
| Brick Class | Minimum Compressive Strength (N/mm²) |
|---|---|
| Class 3.5 | 3.5 |
| Class 5 | 5.0 |
| Class 7.5 | 7.5 |
| Class 10 | 10 |
| Class 15 | 15 |
| Class 20 | 20 |
| Class 35 | 35 |
For general house construction, Class 5, 7.5, and 10 are commonly used. For heavy-duty structures, higher classes like Class 20 and Class 35 are recommended.
Water Absorption as per IS Code
Water absorption is a critical property of bricks since high absorption can cause dampness and weaken mortar bonds. According to IS 1077:
- Bricks should not absorb more than 20% of their weight after 24 hours immersion in cold water for classes up to 12.5.
- For higher classes, absorption should not exceed 15%.
Efflorescence Test as per IS Code
Efflorescence is the white salt deposit seen on brick surfaces. As per IS 3495 (Part 3):
- Nil: No deposit of salt
- Slight: Up to 10% surface covered
- Moderate: 10–50% surface covered
- Heavy: More than 50% surface covered
- Serious: Heavy deposit with flakes peeling off
For quality bricks, efflorescence should not be more than moderate.
Why Builders Must Follow IS Codes for Bricks
- Ensures safety of structures
- Prevents premature failures and cracks
- Helps in uniform construction quality
- Provides legal compliance in government and private projects
- Increases customer confidence in construction quality
FAQs About IS Code for Bricks in Building Construction
What is the IS code for common burnt clay bricks?
The IS code for common burnt clay bricks is IS 1077: 1992.
What is the standard size of bricks as per IS code?
As per IS 1077, the modular brick size is 190 × 90 × 90 mm, and with mortar, it becomes 200 × 100 × 100 mm.
Which IS code covers fly ash bricks?
IS 12894 covers fly ash-lime bricks used in building construction.
How is the compressive strength of bricks tested as per IS code?
Compressive strength is tested as per IS 3495 (Part 1) using a compression testing machine.
Why is water absorption important in bricks?
High water absorption weakens mortar joints and causes dampness. IS code limits absorption to 20% for most bricks.
Can hollow bricks be used in load-bearing walls?
Hollow clay bricks under IS 3952 are generally used for non-load-bearing walls due to their lower strength.
Final Thoughts
The IS code for bricks in building construction provides essential guidelines that ensure strength, durability, and safety in structures. From IS 1077 for common burnt clay bricks to IS 12894 for fly ash bricks and IS 3952 for hollow bricks, each code sets standards for size, strength, and quality. Builders, engineers, and homeowners must always check whether the bricks being used comply with these IS codes. By following IS standards, you not only ensure legal compliance but also guarantee that your building will stand strong for decades.
