SIX

Refurbishment of SIX, a 1990s office building in London that prioritises sustainability through materials re-use and structural retention. The project adds a single-storey vertical extension and a new rooftop pavilion.

Location City of London

Client Great Portland Estates

Architect Barr Gazetas

Status Complete (2024)

GIA 6,044m²

Feature

Key features

Maximising retention

The design maximises the re-use of the existing building, retaining 97% of the structure, including its foundations.

Lightweight vertical extension

A new single storey, steel framed extension, plus a new pavilion structure and external terrace, sits on top of the existing eight-storey reinforced concrete structure.

Sourcing reclaimed steel

We used our Stockmatcher tool to match 24 tonnes of reclaimed steel suitable for reuse, representing 61% of the overall steel tonnage and saving 45 tonnes of embodied carbon.