The Complete Guide to UK Brick Types, Classes and Selection for Your Construction Project
Whether you have construction project plans or are interested in expanding your knowledge about building materials, you shouldn't ignore bricks. Understanding and differentiating the various types of UK bricks helps to determine the best choice for your commercial building, ultimately knowing which type will meet your needs the most.
This in-depth guide on brick types, classes and commonly-used choices for commercial construction should help you get the right bricks for your project.
Understanding the Different Types of Brick Available
Firstly, it's important to note that there isn't just one brick type; multiple types and classes can be used for various construction purposes. You may not be aware of the numerous bricks for sale from suppliers such as Modular Clay Products, but each brick comes with its unique characteristics, composition and advantages.
Therefore, when choosing the right bricks and blocks, understanding what you're looking at from a practical and aesthetic standpoint can ultimately pay long-term dividends. This knowledge may serve you well if you've already decided on what brick colour, brick bonding pattern and texture you've gone for with commercial architecture, but need help figuring out one that has the perfect structural composition.
The brick manufacturing industry has evolved considerably over the centuries, moving from simple clay formations dried in the sun to sophisticated engineered products designed for specific applications. Modern construction demands materials that not only look appealing but also perform reliably under various environmental conditions and structural loads. This is why understanding the classification system becomes crucial for anyone involved in the building trade or property development.
Clay Brick Classes and Their Characteristics
Clay facing bricks are often classified into one of two categories: burnt bricks and unburnt bricks. This fundamental distinction affects everything from durability to aesthetic appeal, and understanding these differences can save considerable time and expense in the long run.
Burnt bricks make up most of the high-quality bricks you may have heard about, but some burnt bricks may also be defective. The burning process involves firing clay at high temperatures, which fundamentally changes its properties and creates a durable, weather-resistant material. This process has been refined over thousands of years, and modern kilns can produce incredibly consistent results that meet exacting standards.
Burnt bricks are broken down into four different categories, each with distinct qualities and appropriate applications. These classifications aren't arbitrary; they're based on physical properties, manufacturing quality and suitability for different construction scenarios.
First-Class Bricks: The Premium Choice
First-class bricks are of the highest quality, with smooth surfaces, as well as hard and well-defined edges. These bricks represent the pinnacle of brick manufacturing, offering exceptional strength, durability and aesthetic appeal. They're fired at optimal temperatures for extended periods, ensuring complete vitrification of the clay body.
The smooth finish of first-class bricks isn't merely cosmetic. It provides better resistance to water penetration, reduces the likelihood of frost damage, and offers a superior surface for rendering or pointing. These bricks are ideal for exposed brickwork where appearance matters, such as façades of prestigious commercial buildings, heritage restoration projects, or high-end residential developments.
Furthermore, first-class bricks demonstrate excellent compressive strength, often exceeding the minimum requirements set by British Standards. This makes them suitable for load-bearing applications in multi-storey structures, retaining walls, and other demanding construction scenarios. Their consistency in size and shape also facilitates easier laying, reducing labour costs and ensuring tighter tolerances in the finished structure.
Second and Third-Class Bricks: Practical Alternatives
Second-class bricks are solid and durable, but aren't as smooth and lack the same quality in edging as first-class bricks. Their shape may also be slightly more irregular. Despite these limitations, second-class bricks still offer considerable value for many construction applications, particularly where aesthetics are less critical or where the brickwork will be rendered or covered.
These bricks work perfectly well for internal walls, garden walls, outbuildings, and other structures where perfect uniformity isn't essential. They meet basic structural requirements and provide adequate weather resistance for most UK climatic conditions. Many builders appreciate second-class bricks for their cost-effectiveness whilst still delivering acceptable performance.
Third-class bricks are much rougher and don't hold up too well in bad weather and moisture-heavy environments. These are ground-moulded and make a good choice for temporary construction, like unburnt bricks. They're sometimes used for backing bricks in cavity wall construction, where they won't be exposed to the elements. However, their use in permanent structures requires careful consideration of the specific application and environmental exposure.
Unburnt and Fourth-Class Bricks
Unburnt bricks, otherwise known as sun-dried bricks, are far less durable and are only used for temporary construction projects. So if you're looking at a permanent building, unburnt bricks are not suitable, given that they also have far less resistance to fire and water. These traditional bricks represent the earliest form of brick-making, where clay was simply shaped and left to dry in the sun.
Whilst unburnt bricks have historical significance and are still used in some parts of the world for low-cost housing, they're unsuitable for the UK's damp climate. They lack the structural integrity required by modern building regulations and would deteriorate rapidly when exposed to British weather conditions.
Fourth-class bricks are often recycled after use and rarely used again for commercial construction thereafter. These bricks have typically been salvaged from demolished structures and may show signs of wear, damage, or mortar adhesion. Whilst they can occasionally find use in landscaping projects or rustic garden features, their structural reliability cannot be guaranteed for new construction work.
Specialist Brick Types for Modern Construction
The range of brick classes above helps break down brick categories, with first-class burnt bricks being the measuring stick for acceptable and stable materials. However, many working within construction, manufacturing, engineering, and similar industries are familiar with specific terms to describe particular brick products.
Concrete bricks are made using sand, cement, coarse aggregate and water. These bricks offer excellent uniformity and can be manufactured to precise specifications. They're particularly popular for internal walls and foundations, where their consistent size and shape facilitate rapid construction. Concrete bricks also provide good thermal and acoustic insulation properties, making them suitable for modern energy-efficient buildings.
Engineering bricks are high-density bricks often used in civil engineering. These specialist products are manufactured to withstand extreme conditions, including high compressive loads, ground contact, and exposure to chemicals or water. Engineering bricks are classified into Class A and Class B, with Class A offering the highest performance. They're essential for damp-proof courses, manholes, retaining walls, and any application where exceptional durability is required.
Traditional and Aesthetic Brick Varieties
Stock bricks are clay bricks that resemble older products made on stock boards, which are iron-faced wood blocks fixed to brick manufacturer benches. These bricks have a distinctive appearance with a slightly irregular texture and subtle colour variations that give buildings character and visual interest. Stock bricks remain hugely popular for residential and commercial developments where a traditional aesthetic is desired.
Waterstruck bricks use water within the moulding process to give them a unique, smooth appearance. This manufacturing technique creates a distinctive surface texture that's prized by architects and designers. The water prevents the clay from sticking to the mould, resulting in a clean, attractive finish that doesn't require the sanding found in some other brick types.
Handmade bricks are similar to facing bricks made using machines but have unique textures due to being hand-thrown in moulds. Each brick carries the subtle imprint of the craftsperson who made it, creating a level of character that's impossible to replicate with mechanical production. These premium bricks are often specified for heritage projects, luxury developments, or buildings where authenticity and craftsmanship are valued above cost considerations.
Modern Innovations in Brick Manufacturing
Fly ash bricks are made using fly ash and water, with very smooth surfaces. This innovative brick type makes excellent use of industrial by-products, offering an environmentally sustainable alternative to traditional clay bricks. Fly ash bricks are lightweight yet strong, provide good insulation, and resist moisture penetration effectively. They're becoming increasingly popular as the construction industry seeks to reduce its environmental footprint.
Sand lime bricks, otherwise known as calcium silicate bricks, are very strong, durable and weight-resistant. These bricks are manufactured by mixing sand, lime and water under high pressure and temperature. They offer exceptional load-bearing capacity, excellent fire resistance, and precise dimensional accuracy. Sand lime bricks are particularly valued in Germany and other European countries, and their use is growing in the UK as awareness of their benefits increases.
Glazed bricks have a smooth, glossy texture, offering tremendous vibrant colour and reflection. The glazed surface is fused to the brick body during firing, creating a permanent, durable finish that won't fade or deteriorate. These decorative bricks are perfect for feature walls, shopfronts, or any application where colour and light play important roles in the architectural design.
Specialised Formats and Dimensions
Long format bricks, also known as Roman bricks, are built to specific dimensions similar to ancient Roman structures. These elegant bricks create distinctive horizontal lines that can make buildings appear longer and lower. They're experiencing renewed popularity in contemporary architecture, where their proportions suit modern design aesthetics whilst referencing classical building traditions.
The dimensions of long-format bricks typically measure around 290mm in length, considerably longer than standard UK bricks, which measure approximately 215mm. This format influences not only the visual appearance but also the construction methodology, requiring different laying patterns and potentially affecting structural calculations. Architects appreciate the design flexibility that long-format bricks provide, allowing them to create striking façades with fewer horizontal joints.
Quality Assurance and Brick Selection
As brick suppliers with a vast network of brick manufacturers, partners and architects, Modular Clay Products take great pride in ensuring each brick we supply undergoes rigorous testing. As a result, we ensure each product is fit-for-purpose and meets the required structural and aesthetic requirements that our clients expect.
Quality assurance in brick supply involves multiple testing procedures, including compressive strength tests, water absorption measurements, frost resistance evaluations, and dimensional tolerance checks. British Standards provide clear benchmarks that bricks must meet, and reputable suppliers maintain comprehensive documentation demonstrating compliance with these standards.
When selecting bricks for your project, consider factors beyond immediate cost. Think about the building's intended lifespan, maintenance requirements, aesthetic goals, and structural demands. The right brick choice balances all these considerations whilst remaining within budget constraints. Consulting with experienced suppliers who understand both the technical and aesthetic aspects of brick selection can prove invaluable in making the optimal choice for your specific application.
Making the Right Brick Choice
Hopefully, this guide has helped you differentiate between specific clay facing brick types, but if you need help finding specific products, look no further. The world of bricks is more diverse and sophisticated than many people realise, with each type offering distinct advantages for particular applications.
Understanding brick classifications, from first-class burnt bricks through to specialist products like engineering bricks and glazed varieties, empowers you to make informed decisions that will affect your building's performance, appearance and longevity. Whether you're planning a small extension or a major commercial development, choosing the appropriate brick type is a decision that deserves careful consideration and expert guidance.