20-23 Greville Street

LONDON, UK, 2023

About the project

Greville Street, a London building referred to by the Financial Times as being “wrapped in a mesh of the past”, exudes nostalgia for the historic city’s original streets that have been lost through the years due to new, consistent urban development. This is juxtaposed with a modern façade material and a focus on sustainability that work together to create a beautifully reimagined hub in the city centre.

The brief for the project concentrated on regenerating this dated 1970’s office building, acting as an alternative solution to demolition, driven by the motive to save as much carbon as possible. Atelier One collaborated with Architects: Groupwork, service engineer Webb Yates and main contractor Red Construction to complete this unique, architectural refurbishment.

The process

The design consisted of a 5 storey rear extension and 2 storey CLT rooftop extension.

Where possible, the existing raft foundation was utilised to support the new rear extension. Due to the building sitting directly above the Crossrail running tunnels, a detailed settlement assessment was carried out to ensure that no damage would be caused. Connections between the existing and new build elements were also detailed to allow for potential differential settlement.

The architectural intent included exposing the structure, removing all ceiling and wall finishes. This meant that all structural elements had to be rechecked for not just additional loading, but also for being exposed to fire. Full intrusive and non-destructive structural investigation was required to determine concrete reinforcement cover and rebar detailing for each column. Each column and beam was then individually assessed and additional cover added only where necessary.

An options study was carried out to look at the best material for the rooftop extension. Timber was chosen due to the low additional weight onto the existing structure and the quick installation time, with cost being comparable to a lightweight steel system.

The building was wrapped with a mesh façade to recreate the previous building on the site. Folded plates were used to provide stiffness, reducing the requirement for supporting structure behind.

The outcome

Greville Street now stands as a demonstration of environmentally conscious urban renewal. The perforated sheet façade encasing the entire building, chosen to showcase the appearance of its previous structural facades. The project seamlessly marries structural innovation with aesthetic appeal, creating a vibrant, dynamic space.