1.8m Allegro® Interlocking Concrete Blocks
Longer blocks for faster wall builds and fewer lifts
Why choose 1.8m Allegro® Interlocking Concrete Blocks?
The 1.8m Allegro® range is designed for projects where quick installation and minimal handling are essential.
- Longer blocks – each full block measures 1,800 mm in length, reducing the number of units and lifts needed to construct walls.
Faster installation – fewer joints lead to quicker build times and a smoother wall finish.
Four block sizes – quarter, half, three-quarter, and full units available, making it simple to stagger joints and build strong corners.
No fixings required – blocks interlock through weight and nib system, ensuring stability without bolts or reinforcement.
A1 fire rated – non-combustible concrete provides up to 120 minutes fire resistance (up to 4 hours with sealed joints).
Built to last – unreinforced construction ensures a 100-year design life, even in aggressive environments.
With 1.8m Allegro® Interlocking Concrete Blocks, you’ll get:
Response from the team within 4 working hours
Full technical support, including product datasheets, O&M manuals and CAD files
UK-wide delivery in 2–4 weeks
Longer blocks for stronger, cleaner walls
If you’re building longer walls and want to reduce time on site, the 1.8m Allegro® range is the perfect choice. Each block measures 1,800mm × 600mm × 600mm and weighs approximately 1,522 kg. With fewer joints per metre, walls look cleaner, install faster, and require fewer lifts to complete.
The system includes four block sizes – full, ¾, half, and ¼ units – so you can stagger joints and create corners without bespoke blocks. This flexibility makes the 1.8m range a reliable option for storage bays, dividing walls, and large-scale retaining applications.
Product Features & Specifications of Interlocking Concrete Blocks
1.8m Allegro® Interlocking Concrete Blocks are designed to save time on site while providing long-term durability.
Block sizes: 1,800mm, 1,200mm, 900mm, and 600mm
A full block measures 1,800mm × 600mm × 600mm, weighing 1,522kg. Additional sizes allow for staggered joints and straightforward corner construction.
Corners: 90° using smaller blocks.
Corners are formed using smaller blocks, ensuring strong connections without the need for bespoke corner units.
Material density: Up to 18 kN/m³
Suitable for storing dense bulk materials such as aggregates, waste, and agricultural products.
Surcharge capacity: Up to 20 kN/m²
Walls can be designed to withstand surcharges of up to 20 kN/m², subject to block height and retained material.
Concrete strength: C40 mix
Ensures high durability and performance in demanding storage and recycling environments.
Connection: Interlocking nibs and recesses
Nibs and recesses lock blocks securely, eliminating the need for additional fixings.
Design life: 100 years
Unreinforced design prevents corrosion, achieving a 100-year design life.
Reinforcement cover: None required
No steel reinforcement is necessary, reducing long-term corrosion risks.
Fire resistance: Class A1, up to 120 minutes (up to 4 hours with sealed joints)
Non-combustible and highly fire-resistant, suitable for fire separation and blast walls.
Edge detail: Chamfered edges
Chamfered edges help reduce visible chipping during handling.
Finish: Smooth mould finish
Smooth front face for a professional appearance, with a hand-trowelled rear face.
Foundation type: RC slab or existing yard slab
Blocks should be placed on a reinforced concrete foundation or stable slab to ensure safe load transfer.
Interlocking concrete block sizes & product range
The 1.8m Allegro® system includes four block sizes, making it simpler to plan layouts while reducing the number of lifts required.
| Height (mm) | Length (mm) | Width (mm) | Weight (kg) |
|---|---|---|---|
| 600 | 1,800 | 600 | 1,600 |
| 600 | 1,200 | 600 | 1,040 |
| 600 | 900 | 600 | 780 |
| 600 | 600 | 600 | 520 |
A Partner You Can Trust
We’ve been supplying precast walling solutions for more than 18 years, delivering over 1,000 projects across the UK. Contractors, engineers, and site teams come back to us because we’re straightforward, dependable, and committed to getting projects done right.
Off-site production means less disruption, less waste, and less dust on site – making projects cleaner, safer, and faster.
Typical Applications
1.8m Allegro® Interlocking Concrete Blocks are ideal for:
Fire & blast walls
Storage bays
Waste & Recylcing
Handling & Installation of Interlocking Concrete Blocks
- Supplied with cast-in lifting pins.
- Orders include 2 × 2.5T spherical head lifting clutches for safe handling.
- Offloaded and placed using a telehandler, forklift, or 360 excavator.
- Installed on a reinforced concrete slab or stable yard surface.
Download the full 1.8m Allegro® Blocks Media Pack
One download with everything you need — brochure, handling guide, and safety data sheets.
Everything you need to plan, specify, and install the product with confidence.
