Concrete Fencing & Ballast
HERMEQ concrete ballast blocks hold hoarding and temporary fencing upright on construction and event sites. Kentledge blocks set behind timber and steel hoarding add the dead weight that solid panels need against higher wind loads, while small concrete fence blocks weigh down mesh fencing in trays and on base plates. The larger blocks have lifting pins, anchors or forklift slots, so a run can be moved and reconfigured as the site changes. Where a perimeter needs more than ballast, concrete barrier systems carry mesh or timber hoarding on a crash-tested base. The range runs from hand-placed fence blocks to 2.5 tonne barrier units, with our kentledge and hoarding blocks manufactured in the UK.
Fence blocks, kentledge blocks and barrier fencing
The range divides by the job the concrete does: small fence blocks add weight to the feet of mesh fencing, kentledge stands behind solid hoarding as a counterweight, and the barrier systems make the concrete part of the fence itself.
Small concrete fence blocks for trays and base plates
Our small concrete ballast blocks are the size of a standard concrete building block and drop into ballast trays or sit on the base plates of mesh fencing panels, which many sites call Heras fencing. They are the choice for open mesh runs on building sites, events and utility works, where the ballast has to be lifted and placed by hand. Pair them with fence stabilisers and ballast trays at gates, corners and exposed stretches of the run.
Compact kentledge blocks for tight sites
The 375kg counterweight concrete block and the 750kg kentledge block take up a small footprint, for pavements, city plots and narrow working strips where a deeper block would obstruct a footway or access route. Choose the lighter block for signage, short hoarding runs and areas without forklift access, and the heavier one for full hoarding runs in wind-sensitive locations.
Heavy hoarding ballast blocks
Our concrete hoarding blocks are larger reinforced kentledge for tall or exposed hoarding, open and elevated sites and industrial perimeters, where wind pressure and site activity are at their highest. They come in several lengths, so the block can be matched to the panel module and to the weight each bay needs. Choose them where the site has room for a deeper block line and a forklift or crane to place it.
Concrete barrier with mesh fencing
The PCM concrete barrier with mesh fencing mounts galvanised, powder-coated mesh panels on a crash-tested precast concrete base. Choose it where a perimeter has to stop vehicles and still leave the work area visible, such as separating pedestrian routes from works or securing a compound beside a road. To separate lanes or work zones where no fence is needed, choose from our road barriers.
Concrete barrier with timber hoarding
The PCH concrete barrier with timber hoarding sets durability-rated timber plywood hoarding on the same crash-tested base, giving a screened perimeter that also resists impact. It suits busy urban frontages and high-traffic locations where the public must not see into the site and loose kentledge behind a hoarding would sit too close to vehicles. Where hoarding beside traffic also has to be tall, quiet and hard to climb, CityWall crash-tested hoarding adds noise-reducing panels and anti-climb protection on a slim footprint.
Concrete ballast blocks for mesh fencing and solid hoarding
Mesh fencing takes light ballast and solid hoarding takes kentledge, because the face of the panel decides how much wind the line has to resist. Temporary mesh fencing lets most of the wind pass through, so small concrete fence blocks in trays or on base plates hold a standard run, with stabilisers added at ends, gates and exposed corners. Solid steel site hoarding and timber hoarding take the full wind load across the whole panel, which a fence foot cannot resist, so kentledge blocks are set behind the line and fixed to the hoarding through stabiliser struts or brackets.
Placing the blocks on the site side keeps the public face flat and clear for pedestrians, signage and printed graphics. The same reasoning applies when a mesh fence is clad in debris netting or a printed banner: the cladding turns it into a solid face, and the ballast has to be increased to match.
Lifting and laying kentledge blocks
Each block in the range lifts in a different way, so the plant and lifting gear on site should decide the block as much as its weight does.
Lifting pins, clutches and forklift slots
The compact counterweight block has a flush-set lifting pin that takes a certified ring clutch or a pin-anchor lifter, so it can be moved without heavy plant. The interlocking kentledge block carries a spherical pin anchor that meets LOLER 1998 when lifted with HERMEQ-approved clutches, and it can also be handled by forklift or lorry-mounted crane. The larger hoarding blocks have an integral forklift slot and a cast-in rebar lifting hook for placing by forklift or crane.
Offloading at delivery
Kentledge comes off the vehicle by Moffett, HiAb crane or forklift, and the clutch for the lifting anchor has to be on site before the first block is lifted. Confirming the clutch and any other offloading accessories at the point of order avoids a delivery standing while one is found.
Setting out a run of blocks
Kentledge and fence blocks are dry laid, so the speed of an installation comes down to the lifting gear and the preparation. Before the job, check these points:
- The block footprint against the width of pavement or working strip that will remain once the run is in.
- A firm, level bearing surface along the line, such as hardstanding or compacted ground.
- An approved clutch or a suitable forklift on site for the lifting points on the blocks ordered.
- The lifting pins, anchors and hooks on blocks returning from a previous job, checked for corrosion, wear and damage before they are lifted again.
- A ballast calculation for the panel height and the exposure of the run.
Popular Categories
Temporary Site Hoarding
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Temporary Mesh Fencing
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Vehicle & Pedestrian Gates
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Frequently Asked Questions
What is the difference between kentledge blocks and Kelly blocks?
There is no practical difference: both names describe a precast concrete weight that holds a structure in place by its mass, as ballast or counterweight. Kentledge is the older term for dead weight used as ballast, and Kelly block is the name many sites use for the same product.
How many ballast blocks does a run of hoarding need?
There is no single figure per panel, because the weight needed depends on the panel height, whether the face is solid or mesh, and how exposed the site is to wind. Tall solid panels on open or elevated ground need more weight per bay than a sheltered mesh run. Our team can advise on the hoarding layout and work out a ballast calculation against the wind loading for your site.
Do concrete ballast blocks need foundations?
No. The blocks hold a fence or hoarding by their weight alone, so they need no trenching, foundations or ground anchors. That makes them the choice on paved public areas, hardstanding and ground over buried services, where digging or driving pins is not allowed.
Can kentledge blocks be reused from site to site?
Yes. Precast kentledge is made for repeat use, and the hoarding blocks have a surface finish suited to repeated deployment on hardstanding and rough ground.
Are concrete fence blocks better than sandbags or plastic blocks?
For most site fencing, concrete is the more economical choice. Concrete fence blocks cost less than rubber or water-filled ballast, and unlike sandbags or loose aggregate they do not split, leak or spill across the site.
Do concrete hoarding blocks interlock?
The 750kg kentledge block, the larger concrete hoarding blocks and the PCM and PCH barrier bases are all interlocking, so a run of them locks into a continuous line. Concrete lego blocks are a different product: large interlocking walling blocks stacked to build bays, partitions and retaining walls. Hoarding blocks are made to sit in a single line behind a fence, or to carry it, as ballast.