House P near Montpellier
This spectacular single-family house in the south of France consists of stacked and partially overhanging rectangular building structures. A modern, architectural design that makes use of the uneven land and, as such, owes its implementation above all to its steel framework.
Flat roofs, large expanses of glass, white walls, clean lines and geometric shapes – at first glance the building in its surroundings looks much like a normal modern villa. Only when you take a closer look you will notice the huge block that protrudes from the complex and rests only on thin angular steel feet protruding from the concrete foundation.
For the architect Frederic Jauvion, the cantilever design was the best and most interesting solution for the uneven plot, which has a height difference of 10 m between the highest and lowest area. Partly because of this geographic condition, no use was made traditional design methods with concrete or wood.
The key to the solution is under the white skin of the 240 sqm building and is not visible at first glance: The structural system of the entire building is based on a steel structure – ArcelorMittal's StyltechTM system!
A case for StyltechTM
The steel skeleton enables an extreme reduction in weight: it is 3 times lighter than a concrete structure with the same surface. The steel structure also offers advantages for construction. Under normal weather conditions, construction would only have taken 6 weeks; however, due to snow, heavy rain and frost, construction of this villa took 4 months.
The 19 tons of steel sections were delivered on a lorry. The sections are assembled like a construction kit: the sections are numbered, the screws are provided in little bags and if you follow the instructions, the assembly is no problem.
Not quite as easy is the preparation of the sections in the workshop of ArcelorMittal Construction, where StyltechTM is produced. Since the system does not allow for any fault tolerance, the sections must be processed exactly as planned. This is only possible if engineers and architects work together closely during the planning phase.
The use of a steel construction system offers a lot of opportunities in terms of creativity and design, especially if the foundation is particularly unfavourable for building projects.
In this case, the architect designed a composition of rectangular, horizontally arranged building members without having to level out the foundation. The lightweight system of steel allowed for a clean assembly, there was no building rubble and the site and its vegetation remained intact despite the interventions.
The main element of the building is the living room that opens out onto a terrace and, thanks to the large windows, offers a panoramic view of the landscape that lies at the foot of the villa.
Inside, nothing points towards the steel structure of the house. The building structures are wrapped in elegant white. Solely the terrace balustrade is made of steel struts.
Sustainable & energy efficient
The client not only wanted a modern house with an architectural design and clean lines, but also an energy efficient building that meets the most current requirements and thus has as little impact as possible on the environment.
In a residential house, the decisive factor is its carbon balance when in use. In this case, it was reduced as much as possible.
As part of the French energy certification process for residential houses, BBC Effinergie, house X was inspected and classified as a passive house, in other words, it generates more energy than it consumes.
To insulate the house optimally, a double insulation layer with a total thickness of 20 cm was used. Between the steel sections, 120 mm thick fibre glass panels were installed. The outer skin of the building consists of wood-fibre insulating boards.
The flat roof is equipped with highly efficient integrated photovoltaic cells that ensure the complete power supply of the house.
The floor plan and room arrangements of the house also meet the most important bioclimatic requirements. While all common rooms are facing south and have an open design, the bedrooms are oriented to the north and only have small window openings. Likewise, the windows of the projecting building, which houses the bedroom and bathroom of the parents, are provided with adjustable louvres.
Text: Constructalia by ArcelorMittal