The Helix occupies a site on the Isle of Dogs, and consists of two elliptical residential towers, respectively 28 and 34-storeys high. The two towers are linked by a podium structure extending up to level 4. The podium levels host residential amenities such as gym, pool, dining room and lounges, and plant rooms.

Key Technical Challenges

The two towers are connected between levels 16 and 24 by an architectural feature called the “spaghetti”, consisting of double-curved steel units cantilevering from each tower. Part of the core of the tallest tower is transferred at podium level to create a clear floorplan for a restaurant. A single level basement sits beneath the building foot print and accommodates 20 car parking spaces, bike storage areas and MEP plant rooms. The basement positioned close to a major Thames Water asset and an HV cable.

• The transfer of the tallest tower core wall at podium level to create space for ground floor restaurant
• Wind response of two towers positioned close one to each other
• Design of spaghetti structure, including second-order non-linear analysis
• Introduction of a swimming pool within the lower tower podium
• Asset protection of a 1500 mm concrete trunk sewer and of a 130kV cable in close proximity to the asset

Key Innovations

Design of spaghetti structure, including second-order non-linear analysis
Transfer of the core of the tallest tower to create enough space for the ground floor restaurant