Copper Bottom

Copper Bottom is a new, better than net-zero, dwelling whose bold sculptural form is an integral part of its radical sustainability strategy. Sitting on a hillside within sight – and cycling distance - of the spires of Oxford, it is intended to be a holistically sustainable exemplar; a carbon-negative, low-maintenance, lifetime home in a rural yet sustainable location. The building’s defining characteristic is its origami-esque copper-clad carapace. This is a carefully crafted brise-soleil, integral to the form of the house: a solar helmet crucial to prevent over-heating of the interior. Its peaks and facets are shaped to modulate sunlight. They protect the generous glazing from summer sun but welcome low sun for solar gain in the winter. What would normally be considered a constraint on design has been turned into an opportunity for architectural expression. The highly sculptural and resonant form derives from the uses it serves; form follows function. Copper Bottom performs as a habitable power station, generating substantially more renewable energy than it demands. Not only is it carbon negative in use, but over time the 30% annual green energy surplus will more than compensate for the carbon footprint of its construction: • To maximise energy production, the house shelters below a single south-facing roof plane supporting a huge array of photo-voltaic panels. • To minimise energy consumption, below its sloping lid the house is a simple two-storey cuboid with a low form factor, built to passive house parameters. • To minimise the carbon footprint of construction, the house is built using structural insulated timber panels with softwood trusses and plywood forming the envelope; the structure is entirely carbon-capturing timber. The cuboid within the solar helmet works equally well for the interior. The slope of the site towards the sun and the views make for a straightforward diagram, with all the living spaces on the south and servant spaces on the north. The interior is pure and simple, all about space and light. It is open plan, focussed on a lofty light-filled double-height space. The finish is crisp, bright and timeless; then for tactility and thermal mass at the heart of the house there is a monolithic tall purple brick wall. This simplicity is also part of the sustainability strategy. Copper Bottom is a long-life, loose-fit, lifetime home. There are no steps on either floor; the ground floor can easily be reconfigured for wheelchair occupancy. Corridors and doorways are wide, ceilings are high, daylight is plentiful. It is easily adaptable to be comfortable whatever the future may hold for its inhabitants. Finally, why copper? Simply because it combines beauty with strong sustainability credentials: • it is less than 1mm thick but very tough, • it is 100% recycled and recyclable, • once patinated, it does not corrode further and will last effectively forever, with a unique and beautiful hue. Here the prepatination has been tailored to a specific verdigris which sits happily in its verdant setting.