Wood Wharf B2 represents an elegant solution for the complex design of a volumetric modular building on a “site that’s not really a site.” The circa 21 storey serviced apartment development is “sandwiched” between the water on its east side and existing concrete bridge/road structures on its west side (see Figure 1). As a result, the building is designed to withstand accidental impact from both a ship and a lorry.
For such a complex and inaccessible site, a volumetric modular delivery is the only sensible solution. 17 storeys of modules are supported by a 1200mm thick transfer slab at 2nd floor level, with an open-plan rooftop restaurant offering prime views of London on top of the modules. Two concrete cores provide global stability.
Modules will be installed by a crane sitting on top of the northern concrete core. The lowest level permanent raft slab spans across several metres of water, with a temporary marine deck, cofferdam and pontoons/barges installed to aid construction logistics. Both cores also have significant “cuts and carves” to bridge over and avoid existing structures, resulting in very complex load paths, both during construction and once the building is completed. These complexities are further exacerbated by raking concrete columns through the podium levels, as part of set-back requirements to minimise the effects of ship impact loading.
The key to the successful design of this project – and why we believe it stands out from the crowd – is the very early engagement of the full consultant and pre-construction team. The client, contractors, architect, engineers, cost consultants, façade specialists, sustainability consultants, acousticians etc were all engaged from the beginning, and were chosen for their previous experience in offsite design/construction. Furthermore, the modular contractor was engaged early under a PCSA so the consultants’ designs and assumptions could be suitably validated.
This early engagement of the project team has meant a much smoother, more efficient process of design development. While there is more advanced funding drawdown of consultants’ fees, the client has reaped the benefits of far earlier risk and cost certainty, helping finalise the contract with their joint venture partner, as well as their funding mechanism in general. Programme benefits will also be gained through the concurrent fit-out of the lower levels (below transfer slab) while the modular levels are installed above.
This project is being used as one of three case studies by the GLA to inform their policy on Circular Economies and it is also on track for a BREEAM Excellent rating.