A social housing project in Norwich, England, hailed as a "modest masterpiece," has won the prestigious Stirling Prize architecture award.
Goldsmith Street, made up of almost 100 ultra-low-energy homes for Norwich City Council and built in seven terraced blocks, was designed by London-based Mikhail Riches with Cathy Hawley.
The Royal Institute of British Architects (RIBA), which launched the annual prize in 1996, announced this year's winner on Tuesday night.
Goldsmith Street consists of rows of two-story houses, bookended by three-story flats.
The architects took inspiration from Victorian streets in the nearby "Golden Triangle" district.
The competition judges, chaired by Julia Barfield, said: "Goldsmith Street is a modest masterpiece. It is high-quality architecture in its purest, most environmentally and socially conscious form."
"This is proper social housing, over ten years in the making, delivered by an ambitious and thoughtful council. These desirable, spacious, low-energy properties should be the norm for all council housing," the judges added.
The development is designed to the stringent Passivhaus standard, which means homes will use very little additional energy for heating or cooling.
Annual energy costs for homes designed to the standard are estimated to be 70% lower than for the average household, according to the RIBA.
In order to ensure the windows echoed Victorian proportions but also met the standard, the architects developed a recessed feature, thereby giving the impression of a larger opening, but with a limited amount of glass.
Letterboxes were also built externally so that front doors would not let in drafts.
Each flat has its own front door, "generous" lobby space for prams and bikes, and a private balcony, the RIBA said.
More than a quarter of the space is communal and a walkway connects residents' gardens.
Parking has been placed on the periphery, "ensuring that people own the streets, not their cars," the RIBA added.
Councilor Gail Harris, Norwich City Council's cabinet member for social housing, said: "This is an incredibly proud moment for Norwich, our strong history of building social housing and our ambitions to raise environmental standards."
Goldsmith Street beat five other nominees on the shortlist to scoop the prize. These included an opera house in Leicestershire, the Macallan Distillery in Scotland and the revamped London Bridge train station.