All Kentledge solutions are not equal
Kentledge based hoarding can be a great solution. Using concrete ballast blocks, Kentledge as they are known, avoids digging. Also avoided are subsurface services, ground repair and even uncovering ordinance. Where a site is to be progressively reconfigured during a build, a kentledge solution enables the hoarding to be easily reshaped.
not equally safe
But all kentledge solutions are not equal. And more importantly not equally safe. Perimeters uses blocks weighing between 750kg and 1300kg. The amount of kentledge we use varies according to the the demands of the situation. A hoarding installation well inland in a sheltered spot would typically require less ballast. A similar site in a coastal location, would require more. Every location is different. That’s why Perimeters has a site specific study conducted by an independent structural engineer for each site. Ensuring the right configuration for the particularities of the location is important.
As importantly Perimeters use cantilever “A-frames” to resist the turning forces and loads. Other kentledge solutions use a timber post bolted to the front of the block. Perimeters’ steel scaffold framework, with all components conforming to the applicable British standards, each component’s strength working in harmony to give a system of known and reliable robustness. Timber posted kentledge solutions use bolts that weaken the strength of the post as they fix it to the block and often the blocks lack fork slots making on site handling dangerous.
Stability is not just about weight
Also a timber post bolted to the front of a block doesn’t spread the combined mass of the hoarding and the blocks. Spreading the load is important. Why? The effectiveness of a mass to resist overturning follows a square law. The distance between the centre and the edge of the mass, is what counts. Think about it,
a ballet dancer with a wide stance can push over a big man on tip toes, but a big man with a wide stance is immovable.
The closer the centre of mass of the combined kentledge/hoarding structure is to the face of the hoarding, the greater that mass will need to be to resist the wind loads pushing on the hoarding.
A 1000kg, 60cm cube block with a post bolted to the front has a centre of mass less than 30 cm from the hoarding. A Perimeters 1000kg block fixed in it’s “A-frame” has a centre of mass over 60cm from the hoarding. The two kentledge may weigh the same. But Perimeters hoarding will resist overturning forces more than 4 times greater.
Especially in city centre locations, space maybe tight. Perimeters kentledge system can be configured to squeeze over 1000kg of ballast per meter. Even where the depth available for hoarding around a site is under 1m, Perimeters has a kentledge solution. In city centres members of the public can be passing any hour night or day. Having a system that won’t let you down is especially important.
Perimeters kentledge, a properly engineered solution, why would you risk the alternatives.