Chart Street warehouse. This is an excellent example of deep retrofitting with a Sylva kit of parts. This project, led by our partners the mass timber specialists, B&K Structures and engineers Heyne Tillett Steel, involved retrofitting a traditional 1930s masonry warehouse.

The original building at 16 Chart Street in Hoxton, London, was a 1930s furniture warehouse. This brick structure, nestled in a mostly residential area, had a robust and utilitarian design typical of industrial buildings from that era. Before its recent transformation, the warehouse had already been converted into office space, but many of its key architectural features were hidden or underutilized. The warehouse's original design included large open floors, which were ideal for storing and moving furniture. These spaces were characterized by their high ceilings and large windows, which allowed for ample natural light-an essential feature for a furniture warehouse where visibility was crucial. The building also had substantial loading bays and large timber doors, facilitating the easy movement of bulky items (Architects' Journal).

Transformation and preservation

When Heyne Tillett Steel (HTS) acquired the building in 2019, they aimed to preserve as much of the original structure as possible while adapting it to modern office use. The architectural firm Ian Chalk Architects was brought in to lead the retrofit. Their approach was to "keep what you can," emphasizing the reuse of existing materials and features to maintain the building's historical character.

Key features retained

Several original features were preserved and highlighted during the retrofit:

Original wooden doors: These were kept in place, maintaining the building's industrial aesthetic and historical integrity.

Large open spaces: The open-plan layout was retained, providing a flexible and spacious working environment.

Brickwork and structural fabric: The original brickwork and structural elements were cleaned and exposed, showcasing the building's robust construction and historical charm.

Modern intervention

To adapt the warehouse for contemporary use, several modern interventions were made:

New entrance and circulation: A new entrance was created, and the circulation within the building was reworked to improve accessibility and functionality.

Roof extension: A stepped-back rooftop extension was added, providing additional office space and enhancing the building's overall capacity.

Perforated steel staircase: A new steel staircase was installed, designed to allow light to penetrate through its perforations, adding a modern touch while maintaining the building's industrial feel.

The prefabricated mass timber elements from Stora Enso, including Sylva™ CLT Floors and Roofs, Sylva™ CLT Walls, and Sylva™ GLT Beams and Columns it was possible to lower the embodied emissions of the retrofit, add structure and strength while also creating an aesthetically pleasing, and functional office environment.

The client, Tom Steel, a structural engineer and future occupant of the building, praised the design for its alignment with their business needs and values. He noted that the space is not only functional but also enjoyable to work in, highlighting the success of the project in creating a user-friendly workspace.

Awards and Recognition

-Hackney Design Award in 2022 and the Retrofit category at the NEW LONDON AWARDS 2022.

-Shortlisted for the Wood Awards in the Buildings, Commercial & Leisure category in 2021

-Structural Timber Awards for Commercial Project of the Year in 2021.

Read more about this project in the Architects' Journal

Performance data

Carbon emissions (all) 34,583 kgCO₂e/m²

Airtightness at 50Pa 8.26 m3/h.m2

Overall area-weighted U-value 0.96 W/m2k

Embodied carbon Total 360 kgCO₂e/m2 (equivalent to 614 tonnes CO₂e)

Operational carbon (over 60 years using FES steady progression 2019 scenario) 728 tonnes CO₂e

 Predicted design life in years 60 years

(Source the AJ)

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