Why Bricks are Different: A Guide to Size and Color

Giovanni Valle is a licensed architect and LEED-accredited professional and is certified by the National Council of Architectural Registration Boards (NCARB). He is the author and managing editor of various digital publications, including BuilderSpace, Your Own Architect, and Interiors Place.

Bricks have a long history in construction, evolving with building trends and construction needs. Since they are durable, easy to use, and cost-effective, they are used in many building projects. Buildings built with brick can withstand years of weathering and keep their traditional appearance.

The type of construction project you are working on and whether your structure will be supporting any amount of weight will determine the kind of brick you will need. With that in mind, it’s important to understand the qualities of bricks to determine which is best for the job.

Bricks are highly versatile, but individual bricks are used for a specific job, so they range in:

Color: red, orange, blue, and white are common brick colors.
Class: Based on quality, bricks are classified from first to fourth class.
Size: Brick sizes range from standard to jumbo-sized.
Purpose: Bricks vary in shape and size based on their intended use.

How and Why are Bricks Categorized?

While the term brick might have once referred to a shaped-clay building unit, it now refers to any clay or stone-based building unit used in construction. Your typical brick for construction measures around 4″ wide and 8″ long. A block is a larger clay-based construction unit often used to lay the foundation of a building and is usually larger than a typical brick.

Most often, bricks are categorized based on color, size, and class. Thanks to modern brick-making and staining methods, color doesn’t necessarily represent quality. Because of this, contractors can focus on the grade of brick needed instead of trying to match visual appeal with quality materials.

However, different grades serve different purposes. Finer, more aesthetically pleasing bricks will be desired for the exterior of structures. Rougher but still durable bricks can be used for their strength in places where their appearance can be hidden. Meanwhile, some bricks will be purely aesthetic and not intended for structural use.

Brick Categorizations Based on Class

First Class Bricks

These are top-quality bricks you will see on the outside of homes or buildings.

Thoroughly burnt and are of copper, dark red, or cherry color
The surface should be rectangular, smooth, and with parallel, sharp, and straight edges with square corners
Bricks should be free from cracks, flaws, or stones
They should have uniformity in their texture
Fingernails should leave no impressions when pushed into them
No lime should show in brick fractures
When two bricks are struck together, they should have a metallic ring
When immersed in cold water for 24 hours, absorption should only be 12–15% of its dry weight
The crushing strength of the brick shouldn’t be under 10 N/mm2 but can vary from region to region

Second Class Bricks

Second-class bricks are less visually appealing but still quality bricks for construction. They will be used in inconspicuous areas or as reinforcement in the structure. They should follow the same requirements as first-class, but with a few exceptions:

Small cracks or distortions are allowed
Slightly higher water absorption of about 16–20% of its dry weight is permitted
The crushing strength should be no less than 7.0 N/mm2

Third Class Bricks

Third-class bricks are used to build temporary structures.

These bricks are under-burnt
They are light-colored and soft
Produce a dull sound when struck against another brick
Water absorbs around 25 percent of their dry weight

Fourth Class Bricks

Fourth-class bricks are used primarily in foundations and floors.

Bricks are over-burnt.
Greatly distorted in size and shape.
Brittle

Brick Categorization Based on Color

Often, when we imagine bricks, they have an iconic red color. However, bricks with different colors exist as well. A lot can be said of the bricks you choose based on their color, and that’s why you need to know what each color means.

The clay used in bricks tends to have different colors based on the geographical location in which it was obtained. This way, it’s possible to come across bricks that take after the color of their clay. However, brickmakers are known to alter the final color by adding different elements that contribute to the bricks getting a specific color.

The yellow or red color is found in most bricks we see today. These colors have become the most widely recognizable brick color in residential buildings. These colors are found in both first- and second-class bricks.

Orange bricks

Mostly common in the Lincolnshire region, orange bricks are suitable for residential buildings. They are strong enough with 30 years lifespan. The bricks are well-colored and reflect the sun’s rays remarkably. Architects and home builders favor these bricks due to their appeal and look.

Blue bricks

Although not as popular as the other bricks, blue bricks have been used occasionally, especially when dealing with recreation centers. Blue bricks are known for their strength and appeal. However, they have a relatively short lifespan of over 20 years. They are suitable for small structures and one-storied buildings.

Soft and light red colored bricks

This is another color that you might run into when searching for building bricks. It might not be as popular as the yellow and red-colored bricks, but they are often preferred in small-scale constructions. Bricks with this color are mostly third-class bricks.

White Bricks

White bricks get their color by mixing more cement with the clay. The cement adds durability to the brick while also altering its color.

Why Do Bricks Have Different Colors and Sizes?

As we have seen, colors are used to classify and categorize the construction bricks. The same can be said about the size. But first, let’s discuss the color variation. Just how do these bricks acquire these colors?

One of the reasons bricks are so widely available and cheap to use is their construction. Keeping things simple, they are primarily made of clay, sand, lime, and Portland cement concrete. These materials are mixed in specific amounts to obtain the desired quality or color of bricks.

Burning the brick at extreme temperatures also affects the color it acquires. Well-burnt bricks tend to be reddish, while over-burnt bricks are brown. Under burnt bricks are often yellowish and are not as strong.

Just like the color, bricks tend to come in different sizes. There are various reasons why this is the case.

Different bricks are designed for different construction purposes. Brickmakers tend to keep this in mind when designing these bricks. Stronger and heavier bricks are often used to lay the foundation and set the groundwork.

Brick Categorization Based on Their Size

Using small bricks might not be economical, and using larger bricks might pose significant risks to the structure. Choosing an optimal brick size helps you achieve your desired project with ease.

Based on their use, bricks will have different sizes that suit them for different building purposes. Below are some common brick sizes available today.

Modular size: The brick’s measurements are 92 x 57 x 194. They weigh 4.2 lbs. and take up 6.86 units per square foot in a wall.

Standard size: This brick measures 92 x 57 x 203. Capable of occupying 6.55 units per square foot and weighing 4.5 lbs., this brick is commonly used in all construction sites.

Jumbo modular: measuring 92 x 70 x 194 and weighing 5.1 lbs., this brick is better suited for laying the ground floor of a structure. It also occupies 5.76 units per square foot.

Jumbo standard: weighing 5.9 lbs. and measuring 92 x 70 x 203, this brick takes up 5.5 units per square foot. It’s also another common brick used in construction.

Jumbo standard PLT 3: With a weight of 5.6 lbs. and 92 x 67 x 203 measurement, this brick makes it perfect for small structures and temporary sheds. It sits on 5.73 units per square foot.

Slim jumbo modular: Known to take up little space, this brick is perfect for filling in the small gaps left after building a wall. It only measures 76 x 70 x 194 and weighs only 4.1 lbs. You can combine this brick with the standard-size brick in your construction.

Queen: Often loved for its beautiful rectangular shape, this brick measures just 79 x 70 x 244. It only weighs 5.6 lbs. and takes up 4.61 units per square foot.

Roman: Roman bricks are thin compared to others, with just 92 x 41 x 295 dimensions. They also weigh 4.7 lbs. The brick is wider than some bricks and takes up 6.00 units per square foot.

Norman: The Norman brick measures 92 x 57 x 295 and weighs 6.4 lbs. The bricks take up only 4.57 units per square foot, which makes them ideal for small-scale construction.

Jumbo Norman: Measuring just 92 x 70 x 295 and weighing up to 7.8 lbs., this type of brick is the best for any tall building or structure. It also takes up 3.84, which makes it ideal for this type of construction.

Slim Jumbo Norman: With a 79 x 70 x 295 measurement and weighing 7.2 lbs., this brick is better for laying the groundwork before the wall. This is the brick for you if you’re building a single-story building.

Modular Economy: The nearly square brick is not meant for huge construction projects, weighing just 6.8 lbs. and measuring 92 x 92 x 194. It only sits on 4.5 units per square foot.

Utility: if you need a multipurpose brick that never disappoints, you must get your hands on this one. This brick is suitable for most construction projects, weighing 10.2 lbs. and measuring 92 x 92 x 295.

Monarch: Known for its slender shape, this brick is amazing for different construction purposes. It only measures 92 x 92 x 397. However, with a weight of 12.5 lbs., it might not be the best for tall walls or structures.

Quad: If you plan to build a strong structure with a longer lifespan, consider using this brick. Weighing 14.2 lbs. and measuring 92 x 194 x 194, this brick suits different construction methods, such as sheds and chimneys.

Ambassador: This brick is perfect for simple construction, measuring 92 x 57 x 397 and weighing 8.8 lbs.. It only occupies 3.43 units per square foot.

Double Utility: Weighing an incredible 21.0 lbs. and measuring 92 x 194 x 295, this brick is suitable for specific types of construction, such as laying the groundwork for the entire wall. The brick is strong enough to handle different weights and pressure.

Double Monarch: Weighing 25.5 lbs. and measuring 92 x194 x 397, this brick is among the heaviest. Many people have used this brick in decorating their driveway, while others have preferred to build their homes with it.

6″ x 4″ x 16″ THRU-WALL: The hollow brick is becoming common, and due to its style, it’s easy to see why. Measuring just 143 x 92 x 397 and weighing 16 lbs., this brick gives you a solid structure and can be used in any construction.

8″ x 4″ x 16″ THRU-WALL: measuring 194 x 92 x 397 and weighing 21.8 lbs., this brick is better suited for single-story buildings. The hollow feature adds to its attractiveness and has been known to be durable.

8″ x 8″ x 16″ THRU-WALL: Known as the heavyweight of the thru-wall bricks, this brick is perfect for strong and durable structures. Measuring 194 x 194 x 407 and weighing 42.0 lbs., this brick is ideal for large-scale constructions.

The 6 Types of Bricks

Unburnt or Sun-dried clay bricks

As the name suggests, these bricks did not go through a kiln. Generally used to build temporary structures, these bricks are less durable and have a reduced lifespan. Making these bricks involves three steps: preparing the clay, molding, and drying.

Since the bricks rely on the heat from the sun to dry, they are less water-resistant not very strong, but are still fire-resistant.

Burnt clay bricks

These bricks are often burnt to reinforce them. However, they also differ in quality, and the skills and experience of brickmakers determine the end product. They can be found in all brick grades.

Fly Ash bricks

Brick manufacturers use fly ash and water to make these bricks. Fly ash bricks are known for their excellent resistance to freeze-thaw cycles and have better properties than clay bricks.

People have labeled it a self-cementing brick because it contains a high concentration of calcium oxide, a property known to help manufacture cement. Their uniform size, fire insulation, lower water penetration, and high strength make them a preferred option to clay bricks.

Concrete bricks

They contain coarse aggregates, sand, cement, and water. Manufacturing these bricks depends on the sizes required by the contractor.

These bricks are better than clay bricks because they can be manufactured on-site and take little mortar to build. They can also be customized with different colors due to pigmentation.

Framed buildings, fences, and facades are excellent examples of structures that fit concrete bricks.

Engineering bricks

Engineering bricks are often preferred on special occasions because they are known for their high compressive strength. Conditions such as low porosity, acid resistance, frost resistance, and shear strength tend to favor using these bricks. Due to their nature, it’s common to find these bricks used in basements where water attacks or chemicals are eminent. These bricks are often known for their high quality and are more durable than clay bricks.

Calcium silicate bricks/ Sand lime bricks

Popularly known as sand-lime bricks, the calcium silicate bricks are made using sand and lime. In construction industries, these bricks are used for several purposes, such as masonry and ornamental work in buildings.

Holes in Bricks

Some bricks are made with holes in them. These holes aid in the manufacturing and use of the bricks. In the manufacturing process, they cause the bricks to have an even thickness that aids even drying.

This also reduces the material that is needed for each brick. This not only lowers the weight, but it also means that it costs less than produce and, therefore, to buy.

The holes aid in the laying of the brick because they allow mortar inside of them, helping to keep them from shifting under stress.

Conclusion

While choosing a brick depends primarily on the intended use, choosing a brick that is strong enough and can withstand any weather while still looking great is another important consideration. Fire and water resistance, ability to withstand high temperatures, and lifespan are as important as the brick itself.

Researching the type of bricks needed for your project and what is available to you is crucial before making any purchase. Having an experienced professional mason around can help you choose the right bricks and avoid settling for low-quality materials.

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