850kg Concrete Ballast Blocks

Versatile counterweights for scaffolding, site security and temporary structures

Why choose 850kg concrete ballast blocks?

These compact counterweights are a practical choice for contractors, event organisers, and site managers.

  • Buy or hire – available for short- or long-term hire, or outright purchase.
  • Greater holding capacity – weighing 850kg, they provide extra stability for scaffolding, hoarding, and site set-up.
  • Linkable blocks – cast-in 68mm diameter holes allow you to connect multiple blocks with scaffold poles, creating heavier combined ballast.
  • Practical handling – fork recess in the base allows it to be lifted with a 2.5T Deha clutch, making transport easy.
  • Better than plastic or water-filled weights – no leaks, no cracks, no refilling; just reliable ballast.
  • Customisable options – we can add Halfen channels, eyebolts, or extra lifting points if required.

With 850kg concrete ballast blocks, you’ll get:

Response from the team within 4 working hours

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Flexible hire or buy options, short or long term 

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UK-wide delivery with optional offload & placement service

Heavy-duty ballast with linking options

When site access is tight or you need flexible anchoring, 850kg concrete ballast blocks give you stability without the need for fixings. 

Each block features a fork recess in the base for easy handling and a cast-in hole through both length and width, allowing you to connect multiple blocks together with scaffold poles.  

This makes them ideal for scaffolding ballast, hoarding, fencing, or any application where a non-invasive counterweight is needed. 

Precast hoarding and ballast blocks on roadside hoarding in London.

Product Features & Specifications of Ballast Blocks

Our 850kg concrete ballast blocks are built for durability, flexibility, and safe handling. Here’s what makes them distinct.

Concrete strength: C40 mix

Manufactured using a high-strength concrete mix, ensuring long-lasting performance even with repeated use.

 

Connection: Flat edges (non-interlocking)

Flat-sided blocks provide flexibility in positioning, without interlocking constraints.

Edge detail: Chamfered edges

Chamfered edges minimise visible chipping and create a cleaner appearance, especially on visible sites.

 

Concrete finish: Mould finish on all visible faces

A smooth mould finish offers a professional look; non-visible faces are hand-trowelled.

Design life: 50 years+

Engineered for long-term durability, with a service life exceeding typical site requirements.

 

Reinforcement cover: N/A (unreinforced)

No steel inside the blocks means no risk of corrosion, ensuring consistent weight and stability.

Sizes & dimensions of 850kg ballast blocks

Compact enough for easy handling, heavy enough for robust anchoring. Supplied with lifting clutch and fork recess for safe, efficient positioning. 

Height (mm) Length (mm) Width (mm) Weight (kg)
600 1,200 545 850
850kg hoarding / ballast-block-render

A Partner You Can Trust

We’ve been providing precast solutions for over 18 years, completing more than 1,000 projects across the UK.

From large-scale infrastructure to specialist event ballast, our customers choose us because we’re straightforward to deal with, quick to respond, and focused on getting projects done right.

We don’t just supply blocks; we provide clear advice, technical support, and practical solutions to help you save time and prevent issues on site.

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Applications for 850kg ballast blocks

The 850kg block is especially popular for scaffolding ballast, where connecting multiple blocks with scaffold poles forms a stable, heavy-duty counterweight.

They’re also commonly used for site setup and security, anchoring hoarding and fencing, and in event management, where a heavier block is required for cabins, stages, or larger structures. With the ability to combine units, they offer a flexible solution wherever non-invasive anchoring is needed.

Events & Festivals

Scaffolding Ballast & Kentledge

Site Setup & Security

“We have consistently been impressed with the service provided by JP Concrete. Their supply of materials has always been prompt and reliable, with excellent communication throughout. The team is professional, helpful, and makes the whole process straightforward. It’s a pleasure working with a supplier who consistently delivers such high-quality products and service levels, and we would have no hesitation in recommending them.”

James Vicary-Ward | Ben Nock

Hire or Buy - the flexible choice

Choose between outright purchase and flexible hire.

  • Short-term hire for events, scaffolding ballast, or temporary site security.
  • Long-term hire for seasonal or ongoing requirements.
  • Outright purchase for contractors who prefer permanent stock.
Precast concrete hoarding blocks on Putney Bridge

Handling & installation of ballast blocks

850kg blocks are simple to move and secure on site.

  • Delivery: UK-wide direct from Nottingham, with optional offload service.
  • Offloading/plant: forklift or telehandler using fork recess.
  • Lifting point: handled with 1 × 2.5T Deha Lifting Clutch.
  • Linking: 68mm cast-in holes allow scaffold poles to connect blocks together.
  • Practicality: combine blocks to create heavier ballast when access restricts larger units.

850kg Concrete Ballast Blocks Media Pack

Our media pack includes the product brochure, handling guide, O&M manual and safety data sheet all in one document.

Everything you need to plan, specify, and install the product with confidence.

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    Questions We Get All The Time

    Here’s what contractors, engineers, and site teams typically want to know, and if we’ve missed yours, give us a call on 0115 895 1120 or email the team at [email protected]
    The 850kg blocks are marginally larger and have cast-in holes for connecting with scaffold poles. This makes them more suitable for scaffolding ballast or when blocks need to be linked.
    Yes, in the UK, “Kelly Blocks” is another term for concrete ballast or kentledge blocks. They’re used as counterweights for scaffolding, hoarding, and temporary works. Our 850kg blocks are often referred to as Kelly Blocks in the industry.
    Yes, the 68mm cast-in holes allow scaffold poles to pass through, enabling the connection of multiple units to increase ballast weight or attach to scaffolding.
    No, the blocks can be handled with a forklift or telehandler using the fork recess, or lifted with a 2.5T Deha Lifting Clutch.
    Yes, both hire and purchase options are available, with UK-wide delivery and an optional placement service.
    Yes, they’re versatile enough for cabins, hoarding, staging, fencing, and scaffolding ballast.
    Yes, cast in C40 concrete with a smooth mould finish and chamfered edges, they’ll last for decades in UK conditions.
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