Steel Foundations

Steel Foundations

Screw Piles

FLI is a major designer and supplier of screwpiles in the UK. These steel foundations deliver many advantages over traditional large concrete bases.

  • Speed, with many complete installs of foundations and superstructures taking a single shift.
  • No excavation or spoil, saving money particularly on soft or contaminated ground.
  • No concrete so no curing time, enabling faster site commissioning.
  • Reduced footprint allows smaller bases in restricted areas.
  • Design flexibility as foundations can bridge existing services allowing structures to be built on congested sites.
  • Sustainability as screw piles are steel and at the end of the installation's life can be removed and either reused or recycled.
  • Installation less effected by low temperatures and wet conditions than concrete.
  • Cost effective solution in soft ground, where traditional piling is more expensive and concrete is technically unsuitable.
  • Capacity in both tension and compression providing an ideal solution where overturning moments are significant.
  • Minimal noise and vibration so working near existing buildings and in conservation areas is possible.

Screw piles were invented by the Irish engineer Alexander Mitchell for lighthouse supports in the 1830s. This original technology was versatile, relatively inexpensive, easy and fast. The same benefits assist modern day projects. Screw piles are a flexible, environmentally friendly and cost-effective technology providing solutions across many sectors.

FLI screwpiles are individually designed by our engineers to suit the ground conditions. The torques are recorded during installation to confirm that adequate capacity has been achieved. Testing is done when required.


FLI engineers develop steel grillage foundations for all sectors, from single post signage to transmission towers. Grillages offer flexible solutions, able to work around existing services and obstructions and enable piles to be used in difficult ground conditions. Grillages, with their steel piles, eliminate the need for concrete. This works with their modular design to deliver install times of hours rather than weeks.

Rapid Deployment Lightweight Grillage

FLI Structures received an 'Innovation in Rail' award from Network Rail for this lightweight grillage range for monopoles and lattice towers up to 30m in height. Collapsible grillages are simple to transport and handle, and allow easier access to restricted sites. The solution separated the functions on the standard design, reducing the weight of the foundations.

Grillages Defining Structures.

Grillages, as the interface between ground and structure can define the nature of the solution. Lean installations with optimised deflection, temporary buildings on soft ground or single pile platforms. Are all made possible by innovative grillage design.