Bored Piles are a ‘Replacement Pile Technique’ – which is a reinforced concrete foundation solution that is effective in supporting structures with a high vertical load by transferring the loads to the higher strength soils at depth, resulting in relatively limited settlements. Unlike pre-cast driven piles, which rely on sections of pre-cast concrete being delivered and driven (most notably by percussive means), bored piles are cast in-situ on site using a hydraulic rig to drill to depth.

This technique is applicable for various constructions such as tall buildings, industrial complexes, bridges and housing – all of which may rely on piled foundations for stability and strength whilst maintaining limited settlements.

The Bored Pile Installation Procedure Explained


Bored pile installation must always be executed by a specialist bored piling contractor, such as Franki Foundations, as the operation is highly complex and requires considerable knowledge and expertise throughout the design and pile construction process.

During the bored pile installation process, the following steps are carried out:

  • Using a bored piling rig, a vertical hole of a required diameter is drilled into the soil to required design depth. As the nature of soil types and site conditions vary, a specialist contractor with extensive industry experience is invaluable to ensure this process is carried out with minimised risks.
  • The bored piling rigs are capable of being fitted with a variety of specialist drilling tools, grabs, and buckets to remove pile arising from the pile bore and advance to design depth through varied ground conditions. Bored piles can be up to 60 metres deep with a diameter of 450mm up to 2.4 metres generally.
  • During the drilling process, a temporary casing may be installed into top section of the pile bore, which remain in place until the concrete is placed. This casing serves to support the sides of the pile bore within the top section, and leaves an upstand above platform level from which to measure pile depth and support the pile cage during placement, if required.
  • After boring to design depth, a radial pile cage (fabricated on site or pre-fabricated) is positioned into the pile bore before concrete is placed. As concreting is completed, the temporary casing is withdrawn.
  • Pile is complete. Follow-on works are required to trim pile to desired cut off level before pile cap or ground beam is constructed by others.

Contact Franki Foundations For More Information


To find out more about bored pile installation, contact Franki Foundations today. With a wealth of experience in constructing deep foundations, our specialists are ready to provide expert advice about bored piles for any complex engineering project. To find out more, get in touch on 01322 936208 or email sales@frankifoundations.co.uk.
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