ReardonSmith Architects Leads the Team in Delivering The Chancery Rosewood In London’s Mayfair

ReardonSmith Architects (RSA) has put the finishing touches to their delivery of The Chancery Rosewood in London’s Grosvenor Square after more than 10 years of dedicated work, transitioning through various phases.

In the course of this time, the practice has helped to create an outstanding world-class hotel while balancing the importance of acting as custodian of the Grade ll Listed building that was previously the American Embassy, enhancing the original architect’s vision for a ‘palace on the park’ and overseeing the ambition to achieve an environmental benchmark amongst five-star hotels in the UK.

The Client’s brief called for the creation of a luxury hotel and a destination that was unrivalled in the capital, and encouraged the team to go beyond the typical aspirations for hotels and consider a wide mix of public functions that would serve to activate the square and translate the hotel into a Mayfair hub.

Unparalleled sustainability credentials were also very much part of the client’s aspirations, and the property has recently received a BREEAM outstanding rating for sustainability development, the UK’s first ever five-star hotel to achieve this.

Initially appointed as ‘Hotel Specialist’ Architect, to collaborate with Design & Lead Architect, David Chipperfield Architects (DCA), ReardonSmith’s primary role at this stage was to consult on hotel design matters including uses, adjacencies, space requirements and the level of specification required to allow the project to progress to detailed design stage. The firm also used its specialist knowledge to create a ‘fit for purpose’ hotel design scheme for review by potential operators.

In 2018, the role of Lead Architect moved from DCA to ReardonSmith with the result that RSA developed the concept design principles established by DCA whilst designing front and back-of-house spaces in detail and leading the wider design team of engineers and interior designers. When Multiplex was appointed as main contractor, ReardonSmith was novated to the company to safeguard the design and engage with the many contracting and sub-contracting specialists through the complex four-year long construction programme.

The building, which extends along the entire Western perimeter of Grosvenor Square, was originally purpose-designed as the new American Chancery in London by the distinguished Modernist architect, Eero Saarinen, and completed in 1960. It incorporated sophisticated features unique to Saarinen’s work which needed to be protected and celebrated. These included his formation of spaces arranged in a “checkerboard” manner resulting in a self-supporting façade and his 45-degree twisting of the conventional structural grid into a diagrid which served to unify the entire building and greatly reduced the need for internal structural columns.

Enabling works were complex and involved innovative solutions. The original façade of concrete cladding and Portland Stone was listed and had to be retained while two new basement levels, in addition to the three already existing, were to be excavated to accommodate services and limousine parking as well as new front-of-house areas. As a result, the façade was suspended over this 30-metre-deep excavation for nearly three years. During this time, the exterior was enhanced with new gold elements, all the windows were replaced, replicating the previous profiles while significantly improving thermal and acoustic performance. The distinctive coping stones on the top of the building were relocated to the new rooftop level to join the restored bronze eagle. Throughout, careful account of the additional strain on the diagrid caused by the new top floor and densely packed plant on the roof had to be made.

Unlike the previous building, which was protected by a defensive glacis, the new hotel is now well connected with the surrounding public realm. With glazed façades at ground level and a new staircase up to the first floor that is clearly visible through the entrance doors, the building now invites people in to explore and engage. In keeping with Saarinen’s vision, the generously proportioned first floor overlooking Grosvenor Square is the main public floor of the hotel, including reception, a bar, lounge, two restaurants and a multipurpose function area, all of which are visually connected by the diagrid. The seven floors above comprise 144 suites which are amongst the largest hotel guestrooms in London. The new top floor accommodates premier suites, the John Adams House at 183 sqm and the Kennedy House at 207 sqm, plus a rooftop bar with views over the square to the East and Hyde Park to the West.

ReardonSmith also technically implemented the Joseph Dirand interior design schemes for the suites, and some of the primary public areas. 

The double-height ballroom, pre-function rooms and spa are accommodated within basement levels one and two. They have a dedicated service infrastructure including, in the case of the ballroom, an entire floor of state-of-the-art plant above, kitchens and prep areas alongside and two very large goods lifts allowing for delivery of such event props as cars.

The ReardonSmith team was led by Patrick Reardon, James Twomey and Irek Pasek. Other members of the project team included: DCA, AKT ll, Hilson Moran, Joseph Dirand, Yabu Pushelberg, Tristan Auer, Albion Nord, BAR Studio, Sagrada, BDP, Gardiner & Theobald, LDI, Gerald Eve, Turley and Twin & Earth.

“The conversion of the former American Embassy into the new Chancery Rosewood is unquestionably one of the most significant hotel projects of the past decade and it has been an honour to work on such a prestigious project, with such an exceptional team. As hotel architects who are highly experienced in repurposing or renovating listed buildings, we are very conscious of acting as custodians of the property while delivering world-class hotels that will meet all operational demands placed on them and fulfil all guest aspirations and expectations to the highest level.”

James Twomey, on behalf of the ReardonSmith team.