A new two and three storey residential development of 105 houses and apartments forming one of the country’s largest Passivhaus certified developments. The project was developed on a Traditional contract for Norwich City Council with Mikhail Riches Architects London office and has generated significant interest as winner of the 2019 RIBA Stirling Prize.
The site comprised a brownfield regeneration in the area immediately to the west of the Norwich inner ring road. Issues typically associated with brownfield development were prevalent, including buried features and historic foundations and wells, contamination and disturbed soils as well as the risk of unexploded ordnance (UXO).
Due to the architectural form, including large and regular window openings and irregular roofscape with occupied roof zone the scheme suited a timber frame, which was also compatible with the Passivhaus specification. Foundations are unconventional for Passivhaus, using suspended high U-value ground floor slab and traditional strip foundations rather than the more typical floating raft, due principally to the history of bombing to the locality and elevated risk which prevented the use of vibro-compaction. Innovative structural engineering was required to realise the architectural vision for the terrace balustrade walls, formed with half-brick perforated wall panels, while preventing the effects of cold-bridging to the internal structure.
Highways and primary drainage were adopted and due to the density of development and risk of solution features a network of adopted culverts are used to attenuate rainwater discharge from the site to the local sewer network.