Constructed in the late 1950s for office use, 49 – 59 Old Street was formerly home to the Post Office and spans seven storeys plus a basement. It is flanked either side by two single storey retail/restaurant units.
Building on a long-standing relationship, Islington Borough Council appointed Diamond Build PLC to refurbish the property into high-specification office space. The aim was to maximise the building’s rental potential in an area of Islington that has become a hub for the creative industries.
A New Lease of Life
The brick facing façade was repaired and the interior reconfigured and refurbished to provide a total of 18,823 sq. ft. of office space. Floors one to six each comprise two self-contained offices and the parquet flooring has been restored throughout. Part of the ground floor has been constructed to allow for light industrial use.
A new improved lobby has been created to mirror the building’s original design with oak panelling and Swedish-designed Bolon flooring.
The project also included the construction of two new roof terraces on the first floor with timber decking and glazed balustrades. A further roof terrace was created at the top of the building providing views over the London skyline. This required the construction of a new dedicated lift, staircase and kitchen area.



Overcoming Challenges
The retail unit attached to the property remained open throughout the works, so Diamond Build liaised closely with the occupier throughout the project to minimise disruption, particularly during the scaffolding stage.
One of the biggest challenges was the design and installation of building services for the refurbished property. Diamond Build had to redesign the MEP infrastructure to increase capacity and managed the installation along with the new service supplies from UK Power Networks. This work also meant the team had to consult closely with the occupier of the retail unit as it shares the same services.
Another complexity was the construction of the large roof terrace at the top of the building along with the staircase and new lift, which ran from the sixth to seventh floor at roof level. This required the roof to be broken out on the top floor but the structure in this section of the building was too unstable to safely complete the work. To overcome this, Diamond Build developed a design with the architect that offered structural integrity without comprising the original design aim.
Outcome:
Speaking about the project, Fiona Monkman, Design Team Leader at Islington Architects, said:
“I have recently completed 49-59 Old Street with Diamond Build and found them an exceptionally professional company to work with. They were extremely conscientious in organising their operations to meet a challenging programme. This was down to the excellent quality of both site management and head-office support services.
“The quality of the workmanship was particularly high and their willingness to collaborate with the design team to resolve site matters in a timely and cost effective manner was outstanding. I would not hesitate to recommend them.”