A CONSCIOUS TOMORROW: Historic building transformed into sustainable office space

Learn how HUT Architects innovatively renovated a Listed building in Clerkenwell into high quality office space, using natural and recycled materials.

Challoner House can be found in London’s Clerkenwell. Originally comprising a pair of townhouses and an iron printing press, the building is situated in a Conservation Area renowned for its architectural and historic interest.

“We knew the building from quite a few years previously. It was effectively two separate addresses that were used as offices for a law firm. Our client bought the building in 2015 and engaged HUT to work up a scheme to bring it up to modern workplace standards,” begins project architect Alicia Sardi. It was important to also preserve the building’s character and history as well as sympathetically transform, extend and thermally upgrade the existing building.

The client, an international residential real-estate company from Sweden, is the landlord and occupies the ground and first floor as their UK headquarters, and they let out the other two floors. The third and fourth floors are designed to a CAT A level, and are separated for private occupiers.

HUT began the original phase of the project in August 2015 for the previous owner, but the most recent works (pictured) were started in December 2022 and finished in June 2024. The building was originally constructed from brick and timber and later, steel. “There was a complete gutting of the building,” explains Sardi. “The existing core was removed, and then a new core was put in a new location to maximize the usage of the floor plan. As the first-floor mansard roof was quite low, so the whole structure was raised by 500mm.”

The existing steel structure has been reused and repurposed to avoid unnecessary waste. The new butterfly roof is constructed using CLT with the vaulted, sculptural form and timber structure left exposed, creating a strong visual connection to the form and heritage of the original building. Breathable materials of sheep’s wool, wood fibre board, hemp and lime render were selected due to their low embodied carbon, thermal benefits and breathability. Internal walls are constructed using Fermacell selected for its recycled content, moisture control and fire resisting properties.

In terms of layout, project architect Todd Courtney adds, “There is a generous entrance, reception and waiting area, making the most of the spacious volumes. The ground and first floor are dedicated for the client, and created bespoke for them. They have a soft colour palette and interior guidelines as part of their branding, which is seen in the pictures.”

The two floors are connected by an internal staircase, which keeps the client’s office space private. Courtney continues, “Alongside working areas, meeting rooms, kitchen and so forth, there is the double height ‘town hall’ theatre. We’ve had great feedback that this is a favourite space of the client’s team.”

The result is a building which is contextual and of its place, celebrating the historical idiosyncrasies whilst significantly improving sustainability and operational carbon costs through the sensitive application of natural materials.

All pictures: © Billy Bolton