This project transformed the home of a vital local hub that had been serving the community for a century from a rundown basement gym hidden deep within a city block into a fully-accessible, visible and sustainable new building. It has been extended up into a luminous new two-storey, street-facing building with an integral public artwork by Artist Caragh Thuring. From here, HCA can expand its already-varied offering of cultural, social and sporting activities and now has the flexibility for multiple hires as a vital source of revenue.

Re-use is a core element, opening up the existing gym volume to the sky and street, admitting daylight, views and transparency through a new roof and rooflights, and creating two new floors of light-filled spaces. At the same time, a new sprung floor, studios, changing rooms, workspaces and clubrooms provide spaces for new audiences.

Economic construction and proprietary systems were adapted in collaboration with Caragh Thuring and the community to transform everyday moments into memorable public spaces, bringing visibility and identity to the organisation, reflecting the importance and culture of the community in this historic and dense inner-city borough.

The old basement was stripped to its concrete structure, relined, tanked and insulated, with a new lightweight steel roof and tall roof lanterns introduced over the gym. Elsewhere, rough concrete soffits, columns and beams remain exposed, intercut with new structures and materials, incisions made for level access, a ramped entrance hall and a lift.

The new building is highly insulated, passively ventilated and optimised for energy. With heating and cooling provided by a new air-source heat pump, it has been designed to decrease emissions as the grid decarbonises. Full accessibility throughout significantly increases the number of people HCA can support, and improved access allows more multigenerational use of the whole building.

The new street frontage offers transparency and connection; it is easy for children to orientate themselves and allows staff to assist when needed. White-painted steel trusses unfold from the street entrance and reception studio into the double-height gym, introducing views deep inside the city block and creating a welcoming filigree lightness over the interior. Construction is legible in exposed timber joists, steels and blockwork, bringing materiality, scale and informal ease of use to the upper floors.

Caragh Thuring’s artwork, ‘Great Things Lie Ahead (2020)’, is integrated throughout the architecture of Holborn House and has been built on old archive materials. A glazed facade is inscribed with local names, events and places, etched between the irregular mortar lines traced from multiple eras of surrounding brickwork. Combined with the exposed steel structure, it results in a kind of ‘Georgian Meccano’ that acts to strengthen the dialogue between the surrounding historic building fabric and the new structure. Evolving with the community, the artwork has become embedded into the fabric of the building through the handwoven acoustic panels lining the gym, the proprietary bathroom tiling transformed with the artist’s gridded patterns and colour and the brightly-coloured metalwork that references Holborn’s forest origins.

Working with LB Camden, 6a and Dan Pearson introduced new wildlife habitats of flowers, climbing plants and a tree into the narrow alleyway. Caragh Thuring’s ‘Great Things Lie Ahead (2020)’ – originating from a line Thuring found in old archive scrapbooks dating back to the 1920s – and children’s games are inscribed into new Yorkstone paving.

The new planters and greenery in the re-lit and re-paved Georgian passageway have created an external room and gardening opportunities as well as homes and habitats for local wildlife.

HCA and 6a architects worked closely in securing the funds for the project. Holborn House has been made possible thanks to the generous support of: Arper, Arts Council England, Bourne Amenity, London Borough of Camden, Camden Council Street Licensing & Highways, City Bridge Trust, Thomas Dane Gallery, Gardenlink, GreenBlue Urban, Hargrave Foundation, HS2 Community and Environment Fund, Hobson Trust, izé, Junckers, Kvadrat, Little Greene, London Marathon Charitable Trust, Marshalls Stone, Mayor of London Good Growth Fund, Power to Change, Sport England, Volker Highways, 3VB Charitable Trust, 29th May Charitable Trust and many private individuals.