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Screw Piles – A Green Alternative to Concrete Foundations

If anything the last decade has taught us, it's that a lot of what our forbearers did was far better for the environment and us as a whole than modern techniques.

It seems that this is even true in the case of geotechnical engineering and the construction of foundations.

The screw piles or pile foundation first came to prominence at the end of the 19th century and became one of the most well-known forms of foundation used throughout the world. It was simple, fast, effective and didn't require the demands alternatives such as concrete does.

If you're not familiar with a screw pile, it's quite a simple but a very effective mechanism. Essentially, it's a screw that's wound into the ground via some earthmoving equipment with a hydraulic attachment. On one end of the pile is a screw or helix and the other is attached to the building. This form of ground anchoring system works with a variety of ground conditions and buildings of all shapes and sizes.

However, one of the main attractions is that a pile system, or helical pile is a far greener alternative to the usual sort of foundation – one which usually requires concrete.

The Reality of Concrete Foundations

The production, transport and the use of concreate is one that causes a lot of environmental impact.  The cement industry is one of the largest contributors to greenhouse gases on the planet, additionally the production and use of concrete causes a number of other problems including soil erosion, water pollution and flooding.

Production of concrete also requires the use of a variety of unsavoury ingredients, while transport of concrete also causes its problems for the environment. 

As an alternative, a helical pile system is a far greener alternative as it only requires a fraction of the manufacturing, a fraction of the transport costs and doesn't create soil erosion problems that the alternative does.

Installation of Foundations

Installation of concrete foundations is a heavy task and one that requires large amounts of very heavy machinery.

While traditional foundations require a lot of soil displacement and removal of excess soil from the site, piles don't. This saves immensely on transportation cost and reduces.

Additionally, materials then need to be brought in to fill the foundation. This means trucks are again used to transport often hundreds or thousands of tonnes of ready mix concrete into a site. Additionally more machinery is used to pour and level the space so the concrete can set properly – it's a pretty intensive effort with a huge carbon footprint.

Pile foundations are a far greener alternative and don't require the use of most of the heavy machinery that a concrete foundation does. 

Additionally, if the foundation needs to be removed further down the line, screw piles can easily be removed from the ground.

The Project

Screw piles also take a lot less time to install and this makes for a shorter project time. In turn, they also require far fewer people to install than a traditional foundation. Fewer people means less energy required and a lower carbon foot print. You can see via the video on how screw piles are installed.

The process is also safer than the one used to install a concrete foundation, which means there is less risk for the work force. Of course, the reduced costs of all of the aforementioned is also something that needs to be mentioned.

Concrete foundations do have their place, however screw piles can be used for a vast amount of the foundation work in modern building. They offer a far more eco-friendly alternative to the traditional methods and are also lower in cost and thus have become increasingly popular in the last decade or so.

Like a lot of things it seems that some of the older methods we've utilised are the greenest and often a lot less work too.