The extensive structural renovation of Walsingham House for KHI Holdings Group includes the addition of two floors
The 1930s office building in the City of London’s Trinity Square Conservation Area, with its classical Portland stone façade, was originally designed by Howard & Souster in 1928-29.
John Robertson Architects’ infilled a lightwell with a new core to create large floorplates for flexible Grade A workspaces. The building’s overall sustainability and energy efficiency has been improved, with the building rated BREEAM ‘Excellent’.
Jra walsingham house london ©hufton+crow 008
The original pitched roof was removed with two new set-back levels added at eighth and ninth floor levels. The three uppermost floors have new terraces with views across London, while at ground level, two new office units have been created which can be converted into retail units as required.
The building’s classical Italianate Portland stone façade has been reworked, with new decorative metal panels echoing the original Art Deco detailing.
New high-performance glazing replaces earlier single-glazed windows, maximising daylight within the office spaces and reducing the need for artificial lighting, while limiting solar gain and energy consumption.
Significant archaeological findings were uncovered during the project dating from Roman, mediaeval and post-mediaeval periods, including the remains of the late 18th-century basement of the East India Company warehouse which once stood on the site.
Jra walsingham house london ©hufton+crow 032
The existing building was an irregular wedge shape, comprised of ‘U’ shaped accommodation surrounding a lightwell, and spanning the basement, ground and seven upper floors. JRA has transformed these spaces into flexible, Grade A office accommodation, meeting BCO standards. The original sloped roof was removed to create a balanced façade and two new levels of offices were added bringing the NIA up to 5,980m2. The three uppermost floors have roof terraces for the occupiers, providing panoramic views towards the river and the Tower of London. At ground level, JRA created a contemporary reception area featuring original artwork by Christian Bahr, with a new entrance which provides level access whilst remaining respectful of the building’s classical façade.
Sustainability has been a key consideration at Walsingham House: an all-electric centralised plant has been installed, along with a bio-diverse roof and new cyclist facilities. The building achieves a BREEAM rating of ‘Excellent’.
Festus Moffat, project director, JRA
1833 ga ground floor 200604
Source: John Robertson Architects
Start on site April 2016
Completion date March 2020
Gross internal floor area 8,150 m2
Gross (internal + external) floor area 8,600 m2
Form of contract or procurement route Design and build
Construction cost £23m,(excluding consultant fees)
Construction cost per m2 £2,672
Architect John Robertson Architects
Client KHI Holdings Group
Structural engineer Campbell Reith
M&E consultant Long and Partners
Acoustic consultant RBA
Project manager JLL
CDM coordinator Bigham Anderson Partnership (BAP)
Approved building inspector Butler & Young
Main contractor ISG
CAD software used Archicad