Bricks have been vital for decades of construction projects. Bricks have provided shape to spaces, walls, and towns since before ancient Greeks and Romans, to our newest concerns in architecture.
Even in today’s industry, we see that there is more than one option when it comes to bricks. The construction industry is so balanced, with age-old clay bricks, as well as new environmentally sustainable properties of materials, and with all the different types of bricks there are, it seems too diverse and vast for one guidebook to cover.
However, whether you are an experienced builder or just someone who is curious about construction, this may be a great pick for you to understand the types of bricks, their properties, and what they are used for.
Table of Contents
What is Bricks?
Bricks are the solid rectangular blocks used for building. They may be made from a variety of materials, including: clay/sand/lime/concrete, etc.; brick is always a key part of our floors, pavements, walls, and more.
Bricks have existed because of their fire-resistant and strong, durable characteristics that have always produced a variety of contexts.
Bricks can be made into a variety of shapes and also produced through a variety of materials that vary based on their context and use.
Every Type of Brick to be Used in Construction
Now, we are going to look at the different types of bricks in order to best us to commonly used in construction:
1. Sun-dried bricks
Sun-dried bricks have probably been around since the dawn of bricks.
Constructed by mixing moist clay with organic substances like straw and leaving them out to dry in the sun, adobe bricks are a cheap and suitable choice for low-bearing or temporary structures. However, they do not have the endurance and firmness of fired bricks.
2. Burnt Clay Bricks
Burnt clay bricks are one of the most commonly used bricks today. Made by moldable wet clay and firing the blocks in a kiln, burnt clay bricks typically offer strength and durability, and are available in classes:
First-Class Brick: A first-class brick is able to be uniform and the same size, shape, and color. A first-class brick should not have any cracks or defects. A first-class brick is usually used for load-bearing walls in exposed conditions.
Second-Class Brick: A second-class brick does not have to be uniform but needs to be adequate in terms of color and size, usable for load-bearing walls under non-exposed conditions.
Third-Class Brick: A third-class brick is irregular, inconsistent, and may be cracked; therefore only used for a non-load-bearing wall.
Fourth-Class Brick: A fourth-class brick is usually made from poor clay materials that have either been underburnt or overburnt, identified as such because they are often crushed and used in ground applications or combined with other materials in a filler.
3. Fly Ash Brick:
Fly ash brick is made up of a combination of fly ash (a by-product of incineration from coal-fired power plants), cement, and water compressed in molds.
They’re an environmentally friendly, low-cost alternative to clay bricks, the common method of building structures.
4. Concrete Bricks:
Concrete bricks are made by mixing cement, sand, and water together and pouring them into a mold. They have a high resistance to fire, which can be helpful in being durable, are ideal for any load-bearing applications, and pavements.
5. Engineering Bricks:
Engineering bricks are made of high-quality clay that is fired at extremely high temperatures to create structural bricks that are very dense, strong, and resistant to water and chemical damage.
These bricks are designed for particular structural applications and are useful in flooding areas or foundations.
6. Calcium Silicate Bricks:
Calcium silicate bricks, also known as sand-lime bricks, are produced using a sand-lime mixture for lightweight blocks and provide excellent insulation.
In addition, calcium silicate bricks resist fire and are made with a smooth finish, and are best used for high-rise buildings as well as thermally insulated spaces.
7. Eco Bricks:
Eco bricks are produced using recycled materials and reducing the use of non-biodegradables like using recycled paper waste or things like plastic bottles – these sustainable blocks can be used for landscaping, non-structural walls, or decorative elements. Eco bricks are becoming more common to use, in part, because they have lower environmental footprints.
Ways to Identify Different Types of Bricks
Identifying bricks is not simply about colour. Below are the factors you should consider:
1. Size
Bricks are usually around the standard 215 mm x 102.5 mm x 65 mm (8.5 x 4.25 x 2.75 in). These characteristics can, however, vary based on regional standards.
2. Colour
Bricks are made in many colours based on the raw material and how they were fired. In high-quality bricks, the colours should reasonably match throughout the brick.
3. Texture
Some bricks have smooth surfaces; some bricks have rough surfaces. The load-bearing bricks usually have smooth textures and sharper edges; the decorative bricks might have some textures or finishes that set them apart from the rest.
4. Sound
Gently tap the brick. If it is of quality and sound, it will make a clear, ringing sound. If the sound resembles a dull thud, the brick might have a defect or damage.
Before starting any masonry project, always consult with a qualified professional to avoid errors that may compromise the structure’s integrity.
Properties of Bricks
Understanding both the physical and chemical properties of bricks is key in selecting the brick that will be the best for construction materials.
1. Hardness:
Bricks should be hard enough to withstand wear and tear; the harder the brick, the more durable it will potentially be.
2. Compressive Strength:
This is a measurement of a brick’s ability to withstand pressure or load. A compressive strength test indicates whether the brick is appropriate for structural use.
3. Absorption Rate:
Bricks should not absorb excessive amounts of water, or they risk being weakened as time passes. Bricks that have low rates of water absorption are ideal in very moist or rainy climates.
4. Thermal Conductivity:
Bricks that are of low thermal conductivity are better insulators of temperature, which will help regulate the interior temperature of structures, ultimately saving energy costs.
5. Efflorescence:
There are white salt deposits that form on the surface of bricks because of moisture. Excessive efflorescence can have a degrading effect on bricks over time.
6. Alkali Resistance:
Bricks should be able to resist alkali chemicals that come from substances like cement. Having good alkali resistance ensures that the bricks do not disintegrate with the alkali chemicals to which they are exposed.
The Nature of Admixtures: AAC Block Hardener and CLC Block Hardener
When bricks are made and create new admixtures came along admixture which are advances in brick brick-making industry, specifically with AAC (Autoclaved Aerated Concrete) and CLC (Cellular Lightweight Concrete).
These hardeners are essential to enhancing the characteristic properties of bricks:
AAC Block Hardener
AAC Block Hardener used solely for AAC block use, it reduces curing time and improves strength and finish. In this context, it is particularly useful for large commercial operations where restoration of building site efficiency and return are their key considerations.
CLC Block Hardener
CLC Block Hardener is specifically designed for lightweight blocks made using foamed concrete. They improve the overall bonded characteristics of lightweight blocks and ensure consistent strength through the blocks, making them ideal for quickly completed residential construction when labour is key.
These hardeners improved the durability of structures by also reducing shrinkage and cracking. Other hardeners mentioned contribute to extensive service lives.
Why Bricks Continue to Be Significant
Even with the evolution of modern construction materials, bricks are still relevant today due to:
Versatility – From residential walls to the tallest towers.
Aesthetics – Bricks will always improve the appearance of the buildings.
Sustainable – New eco bricks and improved admixtures are prevalent, and therefore, bricks are more sustainable.
Structural integrity – High-quality bricks have no alternatives for durability and strength.
Conclusion
The construction industry is constantly changing; however, you can count on bricks being a building block both literally and figuratively!
With the numerous types of bricks available today, from sun-dried bricks to AAC and CLC bricks, builders have so many ways to balance attributes like durability (along with low weight), cost, aesthetic appearance (different colors), and sustainability.
If the construction methods on the various types of bricks are considered, like using an AAC Block Hardener or CLC Block Hardening technologies that are available, designing buildings that are smarter and last longer is just a matter of a little effort, time and consideration.
By selecting the best type of brick for the project, bricks are appropriate and adequate within the project, and considering the quality of the bricks, you have a sound brick structure that should last!
Sandip Agrawal, Polymer Engineer and MD of Sakshi Chem Sciences Pvt. Ltd., leads innovation in construction chemicals, shuttering oils, and industrial lubricants. With expertise in polymer science and eco-friendly solutions, he drives R&D and sustainable advancements, ensuring high-performance products for India and global markets.