A facelift for the Savoy
Designed by architect Thomas Edward Collcutt, The Savoy Hotel opened in 1889 as the dream of Richard D’Oyly Carte who funded his world-class hotel venture with the profits from staging Gilbert and Sullivan in the Savoy Theatre next door. But after 118 years in business, the seven-story Grade 2 listed landmark building on The Strand was in urgent need of a total refurbishment.
The introduction of en suite bathrooms in 1910 resulted in a restructuring that prevented further modernisation. The portion of the facade between the third and seventh floors in the south facing hanging Riverfront facade was extended outwards by 2.5 metres. The external balconies were enclosed creating larger rooms and allowing space to install separate windowless bathrooms and WCs located on the river elevation. Load bearing masonry walls, steel columns and chimney breasts remained within these suites breaking up the space. All suites needed to be redesigned and the entire hotel interior and exterior totally upgraded.
The Savoy temporarily closed in May 2007. BuroHappold Engineering was engaged to provide structural engineering services, working with project architects Reardon Smith. Our greatest challenge was temporarily raising a terra-cotta clad, five storey high portion of the hanging south facing facade (floors three to seven) so that load bearing walls could be replaced with a steel moment-resisting frame system. We determined to do this in two phases each involving half of the hotel’s 60 metre length in the east-west direction, allowing for restoration work to be carried out simultaneously.
The removal of the original masonry walls was challenging as the walls within the suites were supporting the rooftop trusses which supported the hanging facade. We erected ten temporary steel towers each composed of four columns measuring 300mm x 300mm in cross section to support the trusses. The towers took four months to erect for each half of the project and were supported on temporary steel beams installed in the masonry walls of the hotel’s second floor. At the top of the towers were thin hydraulic flat jacks that, when pressurized, slowly moved the trusses upward so that the loads on the trusses would come off the masonry walls and be transferred to the temporary steel framework. The trusses were raised by a maximum of 1 mm in a one-day process and imposed a load of approximately 10,000kN on each of the temporary towers.
Once the loads were transferred from the masonry walls, those old structures were removed and the new moment-resisting frame system was installed. The moment-resisting frame system, composed of UC356 x 406 columns and UB356 x 406 beams with bolted moment-resisting connections, was supported on the hotel’s second-floor masonry walls.
A second series of hydraulic jacks were located atop the moment-resisting frame system; when these jacks were pressurized, the loads of the trusses were transferred from the temporary towers to the permanent moment-resisting frame system, the temporary towers were dismantled, and the facade was lowered back to its original position. During jacking, jack loads, pressures and jack strokes had to be carefully and continuously monitored, with loads being increased incrementally to a final value of the order of 350 tonnes.
Although the original steel hangers that connect the facade to the trusses exhibited signs of corrosion, a survey of the 1910 steelwork satisfied the design team that the hangers were still able to support the facade and thus they were simply repaired and repainted to prevent further damage.
As each half of the facade was raised and lowered, gauges monitored the deflection of the trusses and a series of 30 or so survey prisms were temporarily attached to the exterior of the facade so that any movement could be monitored in three-dimensions via infrared surveying devices. Movement of the facade was limited to 1mm in any direction.
Considerable steelwork around the perimeter of The Savoy’s basement was replaced due to water-related corrosion and new galvanized steel was installed to prevent further corrosion damage. Existing elevators were refurbished and additional elevators were installed providing access to all floors. A large ornate steel and glass cupola was installed in the ceiling of the River Restaurant to bring light from the inner courtyard into the hotel.
The Prince of Wales officially reopened The Savoy on 2nd November 2010 leading to recognition that the project has written a new chapter in the life of one of the most historic, grand and glamorous hotels in the world, bringing The Savoy back to life as a famous London landmark.
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