In addressing how buildings are conceived, constructed and inhabited, Great Notley Primary School is a prototypical architectural response to the demands of the 1992 Rio Earth Summit. A low-lying, turf-roofed triangular building sits discreetly in a landscape. A plimsoll line, or ‘window zone’, circumnavigates its elevations to reference the horizontality of the landscape and emphasise the rises and falls of the building’s roofscape. Inside, six classrooms are organised along one edge of the triangle while all other accommodation is arranged around a central internal court; a move which limits dedicated circulation space to a single corridor to reduce the overall area by almost 10 per cent and so redirect the saving to better specification. Steep rooflights bring light and air deep into building’s centre and ensure that each classroom benefits from southern sunlight. Both overtly modern and subtly understated, the school’s ‘triangularity’ is a distinctive tool to efficiently accommodate the varied spaces demanded by a modern school. The project was won in a Design Council commissioned open competition.