65mm Blue Perforated Class B Engineering Bricks (400 Pack) are high-strength, low-porosity clay bricks designed for demanding structural applications that require superior load-bearing capacity, frost resistance, and low water absorption.

• Below-Ground & Substructure Work: Widely used for building foundations, retaining walls, and damp-proof courses where bricks are exposed to heavy loads and persistent moisture.

• Manholes & Drainage Structures: Ideal for constructing underground chambers, manholes, inspection pits, and sewer systems due to their high durability and resistance to water penetration.

• Load-Bearing Walls: Employed in multi-story or heavy industrial buildings where walls must support substantial structural weight.

• Pillars, Piers & Parapets: Used for structural piers, boundary walls, and parapets that require maximum strength and resistance to harsh weather conditions.

• External Paving & Detailing: Utilized for heavy-duty hard landscaping, steps, or plinth details that need to withstand high foot traffic and freeze-thaw cycles.

Available for collection from our Rugby branch or local delivery using our own fleet.

Delivery is kerbside and the final offloading position is always subject to safe access and the driver’s discretion.

Please tell us before delivery about:

• Narrow roads or restricted entrances
• Parked vehicles or limited turning space
• Overhead cables, trees or other obstructions
• Soft, sloping or unsuitable ground
• Any other access concerns

Enter your postcode on the product page to check your delivery area. We’ll confirm the delivery date after your order is placed.

What does "Class B" mean for engineering bricks?

Class B is a British Standard classification indicating that the brick has a compressive strength of at least 75 N/mm² and a water absorption rate of less than 7%. This makes them exceptionally strong and dense compared to standard facing bricks.

Why do these bricks have perforations (holes) in them?

The holes (perforations) are purposefully manufactured into the brick to ensure an even and thorough burn during the kiln firing process. They also reduce the overall weight of the brick for easier handling on site, and when mortar fills the holes during laying, it creates a stronger mechanical key between courses.

Can engineering bricks be left exposed as a decorative finish?

Yes. While they are primarily functional, their smooth texture and deep, uniform blue-grey color are often used intentionally for contemporary architectural styling, plinths, contemporary garden walls, and industrial-look interiors.

Are Class B engineering bricks frost-proof?

Yes. Because they have a very low water absorption rate (under 7%), very little moisture can penetrate the brick. This means they are highly resistant to freeze-thaw cycles, making them ideal for retaining walls, damp environments, and exposed brickwork.

Do I need special mortar to lay engineering bricks?

Because engineering bricks are dense and have low suction (they don't absorb water from the mortar as quickly as standard bricks), you should use a suitable mortar mix (typically a Designation M4 or Class III/IV mortar) and ensure you do not make the mortar too wet, otherwise the bricks can slip or float out of alignment.

How many bricks are in a standard pack, and how many do I need per square metre?

A pack contains 400 bricks ("400pp"). For standard UK brickwork (using a 10mm mortar joint), you will typically need approximately 60 bricks per square metre for a single-skin wall, or about 120 bricks per square metre for a standard cavity wall.