The word kentledge might sound a little obscure with its origins going back to the 16th century. The original definition is ‘’Weights (often scrap or pig iron) used as permanent ballast on ships’’ however, kentledge is now playing a crucial role in some of the most technologically advanced and ambitious projects of modern times.
For many years hoarding for construction sites and temporary security fencing has been erected by casting the supporting posts into buried concrete footings. This often proves to be time consuming, costly, risky (due to the constant danger of damaging unforeseen buried services) and environmentally suspect because of the need to import readymix concrete (with the associated waste) and to dispose of the spoil form the excavations.
Until recently there were few alternatives options however increasingly engineers and designers are turning to an above ground solution in the form of precast, re-usable concrete blocks. The fence / hoarding posts can be easily drilled and fixed to the blocks without the need to disturb the ground at all.
There are various advantages to specifying a precast concrete kentledge solution for securing hoarding / security fencing –
- Provides a fully engineered solution which can take into account wind loadings etc with the certainty that the counterweight / ballast being provided by the precast concrete kentledge blocks is always exactly what’s been designed for (rather than relying on the integrity on ground conditions)
- It is easier to construct hoarding / security fencing over uneven / undulating ground using free standing concrete kentledge blocks.
- Concrete counterweight / kentledge blocks can be re-used time and time again whereas the concrete used on in ground solutions cannot be recovered and has to be disposed of.
- Above ground solutions don’t pose any risk to existing buried services such as fibre optic cables and power supplies etc.
- It is easier to accurately judge the time it will take to erect site fencing / hoarding because above ground solutions avoid the risk of problems encountered with difficult site conditions / terrain.
- Removing ground mounted fencing / hoarding at the end of a project is much quicker and ‘’cleaner’’ than having to dig out buried posts etc.
- On average above ground solutions are 20% cheaper.
Things to consider when specifying precast concrete kentledge –
- Make sure the supplier / manufacturer is a member of a recognised trade federation such as the BPCF (British Precast Concrete Federation) This will ensure the concrete is manufactured in a quality controlled environment to recognised industry standards.
- Do your research – try to specify a block size type that is already being made. This will not only help with keeping costs to a minimum but will also mean availability of blocks in large numbers at short notice shouldn’t be an issue.
- Make sure your chosen supplier has the capacity to deal with your requirements and is experienced in supplying precast concrete kentledge. Make sure they can also deliver blocks on FORS / Crossrail compliant vehicles with and without crane off-load if required.
Elite Precast are widely recognised as being the UK’s leading manufacturer of precast concrete kentledge having supplied the Olympics, Commonwealth Games, Crossrail and countless other major projects.