This year’s house is definitely urban, cheaper than average to build and even has the possibility of a second revenue stream through a design that allows an advertising hoarding to be mounted on the house. A site-hugging, predominantly single-storey design, Slim House could be built by a HAG-dependent housing association, so tight was the brief and the budget.
“We wanted to be very specific in setting a cost target that would be affordable and developable,” says Hayward. “We set very tight constraints, which are recognisable as housing association standards.”
Although the cost constraints were rooted in reality, most of the 150 architects responding to the competition brief to design terraced homes for a brownfield site showed little regard for them. Slim House’s designer, Pierre d’Avoine Architects, was an exception.
The architect’s design is priced by quantity surveyor Dobson White Boulcott at £42 721 per three-bed unit, or £493/m2 (for a five-unit scheme), which undercuts the build cost of a traditional terraced home by some 5%. Economy comes from the simplicity of Slim House’s structural form. The house has two key elements: the 5 m wide by 25 m long living quarters, punctuated by two courtyards and topped by an Erisco Bauder green roof; and a separate 6 m-long first floor pavilion positioned over the lounge, which creates a double height, galleried space with the potential for full flooring in to create extra live/work space.
The ground floor section relies for structural stability on a row of steel hoops that form the frame, a solution developed with structural engineer Jane Wernick Associates. The frame is clad in 75 mm by 50 mm timber stud panels faced on either side in 12 mm plywood. Floor and roof are also made from pre-assembled timber panels. End elevations are clad in cedar horizontal boarding or shingles.
The first-floor pavilion is made from steel frame and timber panels, faced in zinc cladding, and could be lifted into position on site as a single, prefabricated unit. “Prefabrication gives encouragement for cost, “ says Richard Dobson, partner with Dobson White Boulcott.
“The concept naturally met the cost constraint. We didn’t have to fiddle around with it.” Architect Pierre d’Avoine adds: “For the exhibition, the house has to be built in nine days. But then we thought - why not do it that fast for a real site as well.”
The architect believes the environmental performance of the house could be another attraction. D’Avoine has worked with environmental engineer Max Fordham & Partners to get an anticipated NHER score of 10 and keep annual energy consumption down to less than 50kWh/sq m. That energy efficiency is achieved predominantly by low-tech means: the house’s highly insulated fabric, a site layout with the minimum of exposed external wall, and potential for passive stack ventilation in bathrooms and kitchen, depending on height of surrounding buildings.
Housing association-style budgets do not allow for the inclusion of costly high technology. But d’Avoine has managed to turn his bungalow-on-a-budget into a potential show stopper by mounting a giant screen over the ground floor front facade. The screen shields rooftop gardens from the street and is described as an active facade, or blank canvas.
“It has a steel frame, but is structured in such a way that you could have anything you want on the front of it,” says d’Avoine. Cash-strapped housing associations could rent out the space for advertising hoardings, or developers might use it for public art or planting, he suggests. It could serve a practical purpose and carry street lights, solar panels or satellite dishes.
Even before the unveiling of the show house Yorkshire Metropolitan Housing Association is looking at the feasibility of developing a six-unit scheme in Leeds. “I see it as an urban/suburban hybrid,” says d’Avoine of Slim House. “The house could incorporate a shop, or if there was access to the rear of the site, it could be two small one-person homes. The possibilities are endless.” Others might agree with him.
Source
Building Homes
