London, UK 2015–

30 Grosvenor Square

In 2015 the practice won a competition to convert the iconic mid-twentieth century US Embassy designed by Eero Saarinen. Situated at the heart of Mayfair, the Grade II listed structure was purpose-built in 1960 and is Saarinen’s only UK project. The US Embassy move to a new site has offered a unique opportunity to repurpose the existing building into a world class hotel that includes retail, restaurant/bar, leisure, ballroom and event spaces.

The focal point of the transformation was the preservation of the original scheme, while creating an accessible plan for the new facilities. The new design is the result of a series of investigations into the architecture and intent of Eero Saarinen’s US Embassy, an analysis of the context, and a response to the ambitions and brief for the project. Central to enhancing Saarinen’s vision is the first floor. This piano nobile level has an established relationship with Grosvenor Square and the redevelopment reinforces this dialogue, affirming the building as a ‘palace on the park’.

The redevelopment strengthens the existing design qualities and allow the civic-scaled building to play a more active public role in Mayfair. All security measures and defensive characteristics are removed, allowing the building to reconnect with the public realm of Grosvenor Square’s gardens. The removal of the perimeter glacis introduces a set of steps to negotiate the level difference between the ground floor and the street scape. The west side of the building reopens the mews street, reintegrating the site to its Mayfair surroundings. A new vertically extended storey with a pavilion above forms a new crown for the building, and the landmark gilded aluminium eagle remains on the façade. Retail and restaurant/bar units are located around the perimeter of the ground and first floor, and connect to a newly landscaped public realm, creating an active street front. At ground level, the entrance lobbies and central lobby welcome hotel guests and visitors. The remaining public program is distributed between the basement levels and the roof top pavilion with views over Grosvenor Square Gardens and Hyde Park. The 137 guest rooms are distributed around the central atrium at the upper levels in a mix of standard rooms, standard suites and grand suites.

20152015202045,000 m²Qatari DiarDavid Chipperfield Architects LondonDavid Chipperfield, Louise Dier, Billy PrendergastBenito Blanco, Alasdair GrahamTurley Associates Ltd.Publica Associates Ltd.Building Design Partnership Ltd.

AKT II Ltd.Hilson Moran Partnership Ltd.Gerald Eve LLPGardiner & Theobald LLPReardon Smith Architects Ltd.Buro Four Holdings Ltd.

Twin and Earth Ltd.

CompetitionProject startCompletion dueGross floor areaClientArchitectDirectors in chargeProject architectsHeritage consultantPublic realm consultantLandscape consultantStructural and façadeengineerMEPPlanning consultantQuantity surveyorHotel specialistProject managementSustainability consultant

30 Grosvenor Square