July 20, 2017

Some of the most remarkable modern buildings can seemingly defy gravity with the use of cantilevers. What is the science behind the art?

A cantilever is one of the most useful tools in building design. In essence, it allows part of a construction to stand unsupported. This might sound like it is defying all known laws of physics, but think again. The branches on a tree and even the bookshelves on your wall are all examples of cantilevers in action.

Here, we take a look at how they work along with some of our favourite architectural examples of cantilevers being put to terrific use.

What is a cantilever?

Put simply, a cantilever is a solid construction that is only supported at one end. To fit the definition, it must remain safe and robust without a supporting column or additional bracing.

The advent of steel and reinforced concrete as common construction materials led to increased use of cantilevers in building design, as at last, we had a way of providing sufficient robustness to prevent the protruding part to simply crack and fall.

Look at any modern tower block or hotel and you will see how the balconies jut out into thin air – perfect everyday examples of cantilevers in action.

Some of our favourites

As construction methods and materials have developed, the use of cantilevers has become ever more daring. Here are a few of our favourite examples.

  • 160 East 22nd, Manhattan

From a distance, this 21-floor apartment block looks like any other. But get closer, and you will see that floors 9 and above actually cantilever out above the neighbouring property.

  • U Retreat, Gangwon

This unusual cluster of holiday apartments in a South Korean beauty spot features angular cantilevers that protrude dramatically from the main building, providing some breath-taking 360-degree views across the surrounding landscape.

  • Alpine Cabin, Mount Kanin

A construction does not have to be big to employ a cantilever. This cabin measures just ten square metres and was airlifted by helicopter to its remote location. Designed to withstand extreme weather, it can provide shelter to as many as nine mountaineers at a time. Protruding from the side of the mountain, the aluminium clad building appears to teeter precariously. It must provide one of the most amazing views in the world!

  • Country home, Peru


Tucked away on a 24-acre site in Piura, Peru, stands Casa N, a remarkable country retreat. This is possibly the most gravity-defying example yet. The base is constructed from concrete, and supports three volumes that extend across paths and grassland. These are made from Corten, a variety of pre-rusted steel. The horses that live on the estate take it as normal, but any visitor is left speechless by this remarkable piece of architecture.

  • Splow House, Jakarta

Finally, this cantilever proves that the technique can be used as easily indoors as out, with a little imagination and some design flair. Literally translated as “Split House,” this remarkable achievement was designed by a local architect in Indonesia. It features multiple cantilevered mezzanines, each interconnected by a staircase, and initially looks like the famous impossible staircase created by Lionel Penrose.

Cantilever’s rely on precise calculations and expert engineering. Here at GSE we have a team of expert’s ready to help with your next project, contact us today to find out more.