Our customers found Facit Homes after using an independent architect to design their dream home on a rural Hertfordshire site - a dream home, it turned out, that they were unsure how to build within their budget.
After making a few small adjustments, we managed to bring the costs to the right level whilst maintaining the overall design intent of a beautiful home tailor made to their lifestyle.
One of the special features of this particular project is the steel tree columns that you can see on the right in the picture below; a stunning concept designed by the original architect that we really wanted to bring to life. They support the overhanging first floor and create a covered outdoor space that can be enjoyed whatever the weather.
By using our digital manufacturing process, we were able to detail the steel tree columns to millimetre tolerances and enable a level of craft that really shows in the finished product.
What is a steel tree column?
A column is a vertical pillar that supports the structure of a building. We’ve named these ‘steel tree columns’ because of their unique tree-like appearance and the material they are made from.
The structurally expressive branching arms provide support for the upper level of the home while also becoming part of its aesthetic appeal. These tree columns are particularly impressive because, with corten steel as their primary material, their slim profile will both provide structural strength and weather to a beautiful burnt orange colour in time.
Corten steel is known more commonly as weathering steel due to the layer of rust that forms on the surface of the material but doesn't rust through, protecting the inner steel from further corrosion. It was originally developed for use on railway transport carts in the 1930’s, which needed to be incredibly durable, but has more recently become popular in architectural design for its beautiful colour and texture.
The tree columns were digitally designed in our studio and manufactured from sheet steel using laser cutting and folding machines, then assembled on site as a kit of parts by our construction team.
A larger example of branching steel columns is the design of 'The Tote' in Mumbai, India, as shown in this Dezeen article. Tree columns can also be made from other materials, like the timber in this example by Japanese architect Kensuke Watanabe.
What were the design considerations?
We chose 8mm steel for tighter fold radiuses and a more crisp look, as well as easier handling and assembly. The four, folded 8mm ‘trunk’ elements and four 8mm ‘branches’ provide stability in all directions and create an effective thickness of 32mm while retaining a slender look.
Close collaboration with our long time engineers Milner Associates helped us to reduce down the sizes of the elements and keep the trees from feeling too ‘clunky’. Facit Homes’ in-house design engineers also needed to create a super accurate flat pattern for the fabricators to ensure that all the fixing holes lined up perfectly after cutting and folding.
Galvanic corrosion, also known as bimetallic corrosion, occurs when two dissimilar metals are in contact. In order to prevent this, our design engineers introduced an insulating spacer of a different material between the corten steel and the fixing bolts, which are all A4 stainless steel.
How were they made?
Our in-house designers digitally modelled the columns. Capturing every detail and creating precise measurements for the design, they ensured that the specifications of this model were accurate for the laser cutting and computer controlled folding, and the later assembly.
After supplying the final production information to Lasershape, a precision metal fabrication company, they used their advanced nesting and fibre laser cutting technology to cut the sheet metal into the parts, before adding the 90 degree folds to the trunks.
In order to install the columns, other related tasks in the project programme had to be completed. The supporting concrete pile foundations needed to be poured and set, and the structure that the columns support needed to be in place and propped.
Having been shipped to the site in parts, our experienced on-site professionals assembled the steel columns, bolting the components together following the precise instructions sent from the studio.
The trees were then installed from the top down, first being fixed to a steel beam in the floor above before being secured at the base where any minor tolerances could be adjusted. Overall, the installation took just half a day and now they are in place we have started to finish the Facit Chassis™ above.
To learn more about the manufacturing and construction of our Facit Chassis™ timber frame, read ‘Focus on: The Facit Chassis (part 1)’.