Ground Screws vs Helical Piles

Ground Screws

Ground screws are often marketed as an alternative to traditional concrete foundations and in some situations, they’re a perfectly reasonable choice. But it’s worth being clear about what they are from an engineering point of view.

ground screws

Image credit: Lux garden rooms


A ground screw is essentially a proprietary product.

It’s usually selected from a manufacturer’s range using standard load tables and basic assumptions about the ground conditions, rather than being designed specifically for the structure or the site.


There is usually:

  • Limited or no project-specific design
  • No verification of load capacity during installation
  • An assumption that the ground conditions are suitable and consistent

This makes ground screws ideal for:

  • Lightly loaded structures
  • Temporary or non-critical applications
  • Situations where speed and minimal disruption are priorities

From an engineering standpoint, they are a convenient solution but not a fully verified one.

Ground Screws vs Helical Piles

Helical Piles

Helical piles might look similar at first, but they’re a different thing altogether.

They’re not just selected from a range they’re designed to suit the structure and the ground they’re going into.


Each pile is:

  • Engineered to suit the load requirements of the building
  • Designed based on site-specific ground conditions
  • Installed using controlled torque, which provides real-time verification of capacity


The helical plates (or flights) are not just there to “screw it in” they are critical structural elements that:

  • Transfer load efficiently into competent strata
  • Control settlement
  • Provide predictable performance

This makes helical piles suitable for sites where:

  • Poor or variable ground conditions
  • Restricted site access
  • Tree roots nearby
  • High water tables
  • Sloped or uneven site
  • Retrofitting or underpinning

The Key Difference Between Screw Piles and Helical Piles

The distinction is straightforward:

  • Ground screws are selected from standard manufacturer data
  • Helical piles are designed to suit the structure and the ground conditions
difference between screw piles and helical piles

Why This Matters

The issue arises when the two are treated as interchangeable.

Using a ground screw in place of a designed foundation introduces uncertainty:

  • Settlement behaviour is less predictable
  • Load capacity is assumed rather than demonstrated
  • Long-term performance depends heavily on ground variability

With helical piles, the approach is different:

  • Capacity is derived from design and verified during installation
  • Load transfer is taken into competent strata
  • Performance is more predictable and measurable

Final Thought

For lightly loaded structures, ground screws can be a practical solution.

But once you’re dealing with a building, the foundation becomes a structural element.

At that point, it’s no longer about selecting a product it’s about designing a foundation system with known and verifiable performance.

Related blog: Why Building Control is raising concerns about screw pile foundations

 

Scew Piles for Commercial Builds

In commercial construction, foundations can become a bottleneck, especially when you’re dealing with tight deadlines, poor ground, or restricted access.

Traditional methods involving excavation and concrete can be slow, messy, and disruptive. But there’s a smarter alternative gaining traction across our industry: screw piles.

screw piles log cabin

Screw piles are steel shafts with helical blades that are literally screwed into the ground. No excavation, no concrete, no curing time. For commercial clients, that means quicker programmes, cleaner sites, and fewer logistical issues.

screw pile design

As structural engineers, we regularly recommend screw piles on sites where:

  • Access is limited – Ideal for tight city plots, rear extensions, or infill developments
  • Ground conditions are poor – Performs well on soft, made, or variable soils
  • The site is sloped – Eliminates the need for stepped trenches or complex formwork
  • Environmental sensitivity is a concern – Minimal disturbance near utilities or tree roots
  • Speed is critical – Rapid installation and instant load capacity keep programmes on track
  • Existing buildings are involved – Great for underpinning or strengthening foundations in retrofit projects



screw pile concrete

For developments, especially those in built-up or brownfield areas, screw piles offer a low-impact, high-efficiency solution. They reduce the risk of weather delays, cut out the need for wet trades, and help projects stay on budget and schedule.

Whether you’re planning a new-build, extension, or remedial works, screw piles provide a more predictable and scalable foundation method that aligns with the fast pace of commercial construction.

If your project involves difficult ground, limited access, or a compressed timeline, it’s time to rethink traditional foundations. Screw piles aren’t just an alternative, they’re often the commercial edge you’ve been looking for.