138 Fetter Lane, London

Architect: The Manser Practice
Concept Architects: David Walker Architects
Developer: CLS Holdings
Fabricator: Everglade Windows
Products: GEODE-MX Visible Grid curtain walling, GEODE-MX SG structural glazing, Soleal doors, casement windows


A prominent building in the Chancery Lane Conservation Area in the City of London has undergone a comprehensive refurbishment and extension featuring a range of façade systems from Technal.


The £9 million upgrading programme for 138 Fetter Lane provides around 30,000sqft of Grade A office accommodation and eight new one- and two-bedroom residential apartments.


Technal’s SOLEAL door, two options from the GEODE-MX curtain walling suite and different configurations of casement windows have helped to create a contemporary, classic and high quality appearance for each elevation. The materials used relate positively to the local context, have reinstated the character of the original 1930s building, and enhanced the locality.


A Challenging, High Specification Façade Refurbishment


As part of the refurbishment, the existing building frontage on to Fetter Lane, which had a post-modern composition with superimposed concrete colonnades in front of bronze-coloured glass, was replaced.


The new seven-storey façade features five central bays which project outwards and are flanked by a central bay at either end. The replacement curtain walling was constructed from the GEODE-MX Visible Grid system configured as elongated windows with integrated side hung vents for natural ventilation. This elevation was then defined by masonry spandrels and piers in Portland stone, and white marble-clad columns at either side of the new entrance to the office lobby.


A significant design challenge for the façade project was to engineer and install the mullions for the curtain walling to run the full height of the building and behind the stone colonnades and spandrels on the frontage facing Fetter Lane.


New Windows that Harmonise with the Retained, Original Systems


The existing windows to the offices from the lower ground up to second floor level on the north, south and west elevations were replaced with Technal’s side hung open-in aluminium casement windows in a punched hole configuration and silver anodised finish. The new windows were designed in the same proportions to harmonise with the retained windows on the upper levels.


Creating a Glass-to-Glass Appearance


The GEODE-MX SG structural glazing encloses two new clear glazed infills which extend the office accommodation southwards. It carries large spans up to 3.1m high.


This curtain walling option has a specially-designed ‘toggle’ which removes the need for silicone bonding to hold the glazed units in place, making it faster and simpler to install whilst giving a glass-to-glass appearance. Both façades span four levels from the lower ground floor and each extension has a green roof.


These new spaces overlook the rear courtyard, which has also been reconfigured and landscaped, creating a secluded, peaceful and cloistered ambience adjacent to the Grade I listed St Dunstan-in-the-West Church.


Doors for Outstanding Thermal Performance and High Levels of Security


The SOLEAL high traffic commercial door system was used on the front elevation to access the office lobby; for the entrance to the new apartments to the side; set into curtain walling on the east courtyard office extension, and for the fire exit doors. This product has been developed to provide outstanding thermal performance, stringent levels of security, including to the PAS24:2012 standard, and specification options for areas of heavy use such as apartment buildings and offices.


The Architect’s Perspective

Jonathan Manser, Managing Director, The Manser Practice:


“As there were two distinct uses for this project – high specification offices and apartments – the curtain walling, window and door systems had to be sufficiently sophisticated and flexible to address the needs of both occupiers, whilst complementing the existing building fabric and enhancing its character.”


“The new apartments are located on a busy road so all the systems had to deliver high levels of acoustic protection. The doors also had to be sufficiently robust and versatile to meet the requirements of the two very different applications.”


“This was a complex project but we were completely happy with Technal’s assistance throughout. We are very familiar with Technal’s products. All the systems are performing well on this project and we would definitely use them again on future schemes.”