California greening: inventively embracing green principles, this decent, dignified social housing block in Santa Monica is an important model for the future.

Low-cost social housing in the US is politically and architecturally marginalized, yet there is still a pressing need for decent, affordable accommodation, especially in large urban centres. Colorado Court in Santa Monica marks an intriguing benchmark in the provision of so called 'single room occupancy' (SRQ) housing for tenants on low incomes. The 44 unit housing block is also one of the first buildings in the country to be energy independent, generating nearly all its own energy for electricity, heat and light from alternative technologies. In power-starved California, the impact of such innovation is particularly resonant, and architects Pugh Scarpa Kodama hope that Colorado Court will provide an economical and easily replicable model for green low-income housing elsewhere.

The corner site inhabits a typical disregarded urban backwater close to the Santa Monica freeway exit. Surrounding buildings are largely anodyne, low-rise offices, the exception being a handsome nineteenth-century villa on the north-east edge of the site. Planning is elegantly economical with apartments arranged in three subblocks linked by open walkways to form a rough E shape around a central courtyard. Although at 375sq ft (3Ssqm) apartments are decidedly compact, higher than average ceilings help to mitigate any sense of claustrophobia. Resembling a modest student study bedroom, each flat consists of an integrated living, dining and sleeping space with a fitted kitchen and small bathroom to the rear. Shared areas such as a lounge, laundry and external courtyard offer communal breathing space.

Apartment blocks are stacked over five storeys, giving the complex a Cubist, sculptural quality, with the crisp lines of the quasi industrial walkways breaking up taut planes of buffcoloured render. Photovoltaic panels form mysterious glittering blue membranes on the west side of the building, while on the south facade, an abstract pattern of vertical fins shades and tempers the effects of the Californian sun.

In both siting and form, the building has been designed to exploit passive environmental control strategies such as natural ventilation, maximizing daylight and shading south-facing windows. But it also incorporates a number of innovative energy generation measures, notably a natural gas-powered turbine-cum-heat recovery system that generates the base electrical load and services the building's hot water needs. Photovoltaic panels set in the walls and roof supply most of the peak-load energy demand. This co-generation system converts natural gas into electricity to meet the building's power needs. The same system also captures and uses waste heat to produce hot water and space heating for residents throughout the year. Unused energy from the photovoltaic panels is returned to the grid during the day and retrieved at night as needed. The architects estimate that these energy generation and conservation systems will pay for themselves in less than 10 years and annual savings in electricity and natural gas bills should average around $6000.

Although some might question whether impoverished residents should benefit from expensive energy technologies, the concept of low-cost green housing makes great economic and social sense, for it is precisely people on low incomes who cannot afford high utility bills. Tenants are encouraged to understand and engage with the principles of energy conservation and receive rebates if they under consume their monthly energy allowance. Details such as fluorescent lights which automatically extinguish when a room is not in use, insulation made from recycled newspapers, a bike store, CFC-free refrigerators and a trash recycling room reinforce the evangelical message. As many of the technologies are relatively unproven, it is hoped that in its intelligent exploration of the potential of sustainability, the building will act as a successful demonstration project for developers, planners, politicians, architects and, most especially, the wider public.

Architect

Pugh Scarpa Kodama Architects, Santa Monica

Energy engineer

John G. Ingersoll of Hellos International

Structural engineer

Youssef Associates

Photographs

Marvin Rand