This development on a site fronting onto Highbury Fields in Islington consists of a four-storey block of thirteen flats, two three-storey blocks each of six flats and ten detached three-storey houses.
The site had remained undeveloped since WW2, primarily due to the presence of five railway tunnels. In particular the crown of the large brick Canonbury Tunnel is only 7m below ground level and is therefore highly sensitive to both additional load and the removal of existing loads; the tunnel is also too close to the site boundary to allow space for conventional piling.
The foundation system adopted for part of the four-storey block comprises hand-dug large diameter sleeved and under-reamed piles on both sides of the Canonbury Tunnel along with buried steel bridging transfer trusses. Other foundations comprise balanced raft foundations that maintain the load on the tunnels at historic levels. Deflections of the tunnel walls were monitored throughout construction.
Client: Murphy Group
Architect: Brady Mallalieu
Project Value: £12M
Image 8 courtesy of Fussey Steelwork