The large ‘L' shaped building plot ( 1.422,00m2) near São Paulo, Brazil, was already occupied extensively by an old house and its many extensions and outhouses when architect George Mills was asked to design a new home for the site. The land not occupied by construction consisted of a very beautiful mature garden with mango and other fruit trees attracting birds and providing dense shade. Once the existing buildings were demolished, it became apparent that the reoccupation of the previously built-on areas was the only way to maintain the luscious vegetation. So it was that not one single tree was removed during building operations. Building approval was therefore achieved much more quickly than would have been the case had the architects decided to seek approval for the removal or transplant of existing trees.

The building footprint therefore followed almost exactly that of the previous construction, following closely the west and south boundaries of the land. This meant that both east and north faces could be extensively glazed with views out onto the garden and pool. These openings are protected by wide overhanging eaves, reducing the summer sun, yet still allowing the winter sun to reach all living spaces.

The house owners, as part of the original brief, had asked for large interconnected living spaces which could comfortably accommodate groups of friends and family of up to 50 or 60 people. Since the house was completed, this aspect has been widely used and not even heavy tropical summer downpours have interrupted these gatherings.

The two-storey steel frame with epoxy primer paint was delivered and erected on site in approximately three weeks. While the steelwork was being prepared in the factory.

The two-storey steel frame with epoxy primer paint was delivered and erected on site in approximately three weeks. While the steelwork was being prepared in the factory, the preparations on site were under construction, concrete pile foundations ( the land is on the site of a former swamp), concrete blocks and beams, and even the reinforced concrete ground slab, with electrical and plumbing work, was ready for the arrival of the steel structure.

From the designers point of view, the quality control achieved by greater prefabrication and factory production plus the economies in time during the building process more that compensate for any small additional costs when compared to traditional concrete methods.

The use of the steel frame in this context has the advantage of reducing messy onsite operations which could damage the existing vegetation.

For the end user, the efficiency, organization, and speed of construction means that his time in previously rented accommodation ends at an earlier date.

The use of lightweight steel reinforced concrete floor and roof panels designed to be carried by two people and which avoids the necessity for props and scafolding during the pouring of the concrete.

The use of an Evalon coated flexible membrane, extremely resistant to ultra violet rays, as waterproofing on the roofs, means less worries during installation and an almost maintenance-free life. This same membrane makes for simple details around roof openings, whether for service routes or skylights.

Key information

Number of storeys	2
Living area (m2)	741m2
New-build home

Location of steel solutions

External wall
Floor
Walls
Cladding
Light steel sections
Roof
Water systems
Interior design
Steel frame
Storage Tanks

Types of steel used in the building

Long carbon steel
Metallic coated flat carbon steel
Organic coated flat carbon steel
Stainless steel