4.9 QUALITY CONTROL OF BRICKS
Bricks are widely used masonry units in construction. Quality control ensures that bricks meet strength, durability, dimensional accuracy, and durability standards, providing safe and long-lasting masonry structures.
4.9.1 Objectives of Brick Quality Control
- Ensure uniform size, shape, and surface finish.
- Achieve adequate compressive strength for load-bearing walls.
- Minimize water absorption to prevent dampness and efflorescence.
- Detect defective or under-burnt bricks.
- Ensure compliance with BIS standards.
4.9.2 Types of Bricks
Type |
Description / Use |
Clay Bricks |
Red or burnt clay bricks used in walls and partitions. |
Fly Ash Bricks |
Made of fly ash, lime, and gypsum; lightweight and durable. |
Concrete Bricks |
Made of cement and aggregates; used for non-load-bearing walls. |
Engineering Bricks |
High-strength, low-porosity bricks for retaining walls and damp-proofing. |
4.9.3 Laboratory Quality Tests for Bricks
S. No. |
Test Name |
Description / Objective |
Typical Requirement / Acceptance Criteria |
Standard Reference |
1 |
Compressive Strength Test |
Determines the load-bearing capacity of brick |
≥ 3.5 MPa (common), ≥ 10 MPa (engineering bricks) |
IS 3495 Part 1 |
2 |
Water Absorption Test |
Measures porosity and durability against moisture |
≤ 20% by mass (clay bricks), ≤ 15% (fly ash bricks) |
IS 3495 Part 2 |
3 |
Efflorescence Test |
Detects presence of soluble salts that can cause white deposits |
Nil to slight (Grade 1) |
IS 3495 Part 3 |
4 |
Dimension and Tolerance Check |
Ensures standard size and uniformity for easy masonry work |
Tolerance ±3 mm in length/width, ±2 mm in height |
IS 1077 |
5 |
Hardness / Soundness Test |
Strike brick lightly; should produce a clear ringing sound |
Clear ringing indicates good quality |
IS 1077 |
6 |
Shape and Surface Defect Inspection |
Checks for cracks, warping, under-burning |
Bricks should be rectangular, well-burnt, uniform |
IS 1077 |
7 |
Impact / Drop Test |
Checks resistance to handling and transportation |
Should not break when dropped from 1 m height |
IS 1077 |
4.9.4 Field Quality Control Measures
- Reject under-burnt or defective bricks before masonry work.
- Store bricks on raised platforms to avoid contact with soil moisture.
- Ensure uniform soaking of clay bricks before laying (for water absorption control).
- Maintain proper mortar-to-brick bond for masonry strength.
- Monitor daily compliance with size, shape, and strength requirements.
4.9.5 Acceptance Criteria for Bricks
Property |
Requirement for Common Clay Bricks |
Requirement for Engineering Bricks |
Compressive Strength |
≥ 3.5 MPa |
≥ 10 MPa |
Water Absorption |
≤ 20% |
≤ 15% |
Efflorescence |
Nil to slight |
Nil to slight |
Dimensions (L × W × H, mm) |
190 × 90 × 90 ± 3 |
230 × 110 × 76 ± 2 |
Shape & Surface |
Rectangular, uniform, well-burnt |
Rectangular, uniform, well-burnt |
4.9.6 Important BIS Standards (Latest Revision)
Standard No. |
Title / Description |
IS 1077 |
Common Burnt Clay Building Bricks – Specification |
IS 3495 Part 1 |
Methods of Tests of Burnt Clay Building Bricks – Compressive Strength |
IS 3495 Part 2 |
Methods of Tests of Burnt Clay Building Bricks – Water Absorption |
IS 3495 Part 3 |
Methods of Tests of Burnt Clay Building Bricks – Efflorescence |
IS 2180 |
Fly Ash Lime and Fly Ash Lime Cement Bricks – Specification |
ASTM C62 |
Standard Specification for Building Brick (Solid Masonry Units) |