Source: Jack HobhouseSource: Jack HobhouseSource: Jack Hobhouse1/3show captionThreefold Architects has completed a 23,000 sq.ft retrofit of 12 Little Portland Street, a grade II-listed building close to Oxford Circus, for The Crown Estate.The project seeks to revitalise the 1920s neo-classical office building, incorporating flexible office spaces and upgraded energy performance measures while preserving its heritage features.The design is intended to address post-Covid workspace trends, focusing on smaller, more flexible spaces suited to hybrid working. According to Threefold, the scheme aims to diversify The Crown Estates commercial portfolio by attracting a mix of tenants through inclusive layouts and amenities that promote collaboration and well-being.Significant upgrades have been made to the buildings thermal performance, with new mechanical and electrical systems installed, including a high-efficiency recovery condenser and modernised ventilation systems.Heritage features such as period windows and plasterwork have been refurbished or echoed in new design elements. A full faade restoration was undertaken, alongside the replacement and refurbishment of glazing, which contributed to achieving a BREEAM Very Good rating.Existing materials, including raised access floors, were catalogued and reused where possible, aligning with circular economy principles.Source: Jack HobhouseSource: Jack HobhouseSource: Jack HobhouseSource: Jack HobhouseSource: Jack HobhouseSource: Jack HobhouseSource: Jack Hobhouse1/9show captionInternally, the six floors of workspace are designed to accommodate contemporary work practices. Threefold describes the spaces as a mix of task-specific work areas, breakout zones, and collaborative areas, with natural materials and planting used to create a comfortable environment.A key addition is a new roof terrace, which transforms previously unused space into an outdoor area for events and relaxation, offering views of central London.The terrace includes planting to support The Crown Estates Wild West End strategy, aimed at improving air quality and urban biodiversity. Features such as bee blocks and insect habitats have also been integrated.Project dataClient: The Crown EstateArchitect: Threefold ArchitectsProject Manager: Dendy ByrneStructural Engineer: HTSM&E: WPPEnvironmental: WPPHeritage Consultant: Donald Insall AssociatesPlanning Consultant: Gerald EveCompleted: October 2024Gross internal area: 23,000 sq/ftPhotographs: Jack HobhouseSuppliersLino: GerfloorTerrazzo: Inopera Kitchen worktop, Diespeker for StairsFurniture: Rawside, Ondaretta, Vitra, Pearson LloydSanitaryware: CrosswaterRecycled Paint: Paint 360Tiles: GrestecBespoke Joinery: Falkus JoineryTerrace Planters: RaaftWall lights: Holloways of Ludlow/ ArtimedeDecking: RaaftTerrace Handrails: BA SystemsBlinds: WaverleyInsect hotels: Green and blueBird bricks: manthorpe