All You Need to Know About Bricks

Bricks are one of the oldest and most widely used building materials in the world. From small residential homes to large commercial buildings, bricks form the backbone of many construction projects because they provide strength, durability, fire resistance, and thermal comfort.

However, choosing the correct brick is not always simple. In South Africa, bricks are commonly identified by different sizes, materials, and industry codes such as NFX, NFP, FBA, and others. Understanding these differences helps builders, homeowners, and professionals select the right product for the job.

What Are Bricks Made From?

The two most common brick materials used in construction are clay and cement-based materials.

Clay Bricks

Clay bricks are manufactured from natural clay that is shaped and fired at high temperatures in a kiln. The firing process hardens the clay and gives the brick its strength and durability.

Advantages of Clay Bricks

• Excellent durability and long lifespan

• Good fire resistance

• Natural thermal properties, helping regulate indoor temperatures

• Low maintenance

• Available in different finishes and colours

Clay bricks are commonly used for external walls, internal walls, face brickwork, and structural applications.

Common South African clay brick categories include:

• NFP

• NFX

• Face bricks (FBA, FBS, etc.)

Understanding Brick Codes

Brick codes are used to describe the type, quality, and intended use of bricks.

NFP Bricks (Non-Facing Plastered)

NFP stands for Non-Facing Plastered.

These bricks are designed to be covered with plaster or another finish. They are not manufactured to provide an attractive exposed surface.

Typical uses include:

• Internal walls

• External walls that will be plastered

• Boundary walls that will receive a finish

• General building work

NFP bricks are usually selected where appearance is not important because the brick will be hidden behind plaster.

NFX Bricks (Non-Facing Extra)

NFX stands for Non-Facing Extra.

NFX bricks are generally a higher-quality non-facing brick compared to standard NFP bricks. They have improved dimensional accuracy and strength characteristics.

Typical uses include:

• Plastered external walls

• Internal structural walls

• Areas where better brick consistency is required

Because of their improved quality, NFX bricks are often preferred by contractors who want easier laying and better alignment.

FBA Bricks (Face Brick Appearance)

FBA stands for Face Brick Aesthetic.

These bricks are manufactured to be visible after construction. They have a more controlled appearance, colour, and texture.

Typical uses include:

• Exposed face brick walls

• Decorative brickwork

• Feature walls

• Homes where no plaster finish is required

Face bricks require careful selection because colour variation and texture become part of the final appearance.

Other Face Brick Categories

Other codes may include:

FBS – Face Brick Standard

Standard face bricks used for exposed brickwork where appearance and consistency are important.

FBX – Face Brick Extra

A higher-quality face brick with tighter manufacturing tolerances and a more uniform appearance.

Imperial Bricks

The term imperial brick refers to the traditional South African brick size that was historically based on imperial measurements.

A typical imperial brick is approximately:

222 mm long × 106 mm wide × 73 mm high

(Actual dimensions can vary slightly depending on manufacturer.)

Imperial bricks have been widely used in South Africa for many years and remain common in renovations and older buildings.

Advantages:

• Familiar to many builders

• Works well with traditional construction methods

• Suitable for renovations where matching existing brickwork is required

Maxi Bricks

A Maxi brick is a larger-format brick designed to reduce the number of bricks required per square metre.

A typical Maxi brick is approximately:

290 mm long × 90 mm wide × 140 mm high

The larger size means:

• Faster wall construction

• Less mortar required

• Reduced labour costs

• Fewer joints in the wall

Maxi bricks are popular in modern construction because they can improve building speed.

A Maxi brick wall may look different from an imperial brick wall because of the reduced number of courses and joints.

Concrete Blocks

Concrete blocks, sometimes called cement blocks, are manufactured using cement, sand, and stone aggregates.

They are generally larger than standard bricks and are available in different thicknesses.

Common uses include:

• Foundation walls

• Retaining walls

• Boundary walls

• Industrial buildings

• Large structural walls

Advantages:

• Strong and durable

• Fast installation due to larger size

• Cost-effective for large areas

• Available in different strengths

Concrete blocks can be solid or hollow.

Solid vs Hollow Blocks

Solid Concrete Blocks

Solid blocks contain concrete throughout their volume.

Used for:

• High-strength applications

• Heavy-load walls

• Foundations

Hollow Concrete Blocks

Hollow blocks have internal cavities that reduce weight.

Benefits:

• Easier handling

• Lower material cost

• Improved insulation

• Faster construction

Brick Strength and Quality

Bricks are not only chosen by size and appearance. Their strength is also important.

Factors affecting brick performance include:

• Manufacturing process

• Material quality

• Firing temperature (for clay bricks)

• Cement mix design (for concrete products)

• Water absorption

The correct brick must match the requirements of the building.

For example:

• A decorative face brick may be selected for appearance

• An NFP brick may be selected for a plastered wall

• A stronger block may be required for structural work

Clay Brick vs Cement Brick: Which Is Better?

There is no single "best" brick. The correct choice depends on the project.

Clay Bricks

Best for:

• Traditional homes

• Face brick finishes

• Long-term durability

• Fire-resistant construction

Cement Bricks / Blocks

Best for:

• Fast construction

• Large structures

• Cost-effective walling

• Foundations and boundary walls

Brick Quantities and Building Estimates

When estimating brickwork, several factors must be considered:

• Brick size

• Wall thickness

• Mortar joints

• Wastage

• Openings such as windows and doors

As a general guide, brick quantities differ depending on the brick type. A larger Maxi brick requires fewer units per square metre compared with a standard imperial brick.

A professional estimate should consider the exact manufacturer’s dimensions and project specifications.

Understanding bricks goes beyond simply choosing a colour or size. The difference between an NFP, NFX, FBA, imperial brick, Maxi brick, or concrete block affects the strength, appearance, cost, and construction speed of a building.

Choosing the correct brick ensures a better-performing structure, reduces unnecessary costs, and helps achieve the desired finish.

Whether building a new home, renovating an existing property, or preparing a construction estimate, knowing your bricks is an essential part of successful building.