Lewis completes construction on first phase of Amazon South Lake Union Headquarters
Seattle – Lease Crutcher Lewis completed construction of the shell and core as well as the interiors of four buildings as part of Amazon’s new corporate headquarters in South Lake Union. The project was developed by a joint venture led by managing partner Schnitzer West in conjunction with Vulcan Inc. Project completion was three weeks ahead of schedule and significantly under budget.
The four buildings include two at six stories, one at five stories, and a partial reconstruction of the century-old Van Vorst Building, which previously served as a stable for delivery-wagon horses. At Van Vorst, the wood structure was demolished bay-by-bay while the masonry exterior remained standing, with each bay being temporarily braced and then replaced with structural steel. The complex includes below grade parking, and the buildings together total nearly 425,000 square feet.
Additional phases of the Amazon headquarters are currently under construction. In order to facilitate smooth communication and coordination across all phases, Lewis participated in bi-weekly meetings that included the owner, SDOT representatives, and representatives from the other construction projects covering topics from street use, truck routes, pour and delivery schedules to parking, pedestrian access and deliveries. The contractors had to coordinate the routing of services to all of the buildings which, for example, required networking of all the teledata cables.
Lewis used Virtual Design & Construction / Building Information Modeling (VDC/BIM) extensively. One focus was to ensure efficient placement of the more than 10,000 embed plates and anchors for the concrete slab edges, slabs, columns and walls. With the model, Lewis was able to pull the required embeds from stock in advance of each pour to have exactly what was needed on site and to layout and place each embed on the formwork.
VDC/BIM was also used for the very complex public plaza – a series of concrete steps, walls, and colored concrete paving in unique geometries, constructed over a post-tensioned concrete deck. It was designed with circular stairs that have a radius of 150 feet or more. The construction was further complicated by the stair risers, which are each inclined one inch giving the risers a different radius on the top than on the bottom. Each stair steps back 12 inches so each riser is a different radius from the next. Using VDC/BIM, Lewis produced a full scale template that laid out each stair riser allowing the carpenters to quickly stencil and cut out the risers to the correct shape. Lewis saved considerable money in its Guaranteed Maximum Price contract by reducing the number of hours necessary to produce the stair forms.
Using the Lean Construction Institute’s Last Planner system allowed Lewis to finish the early tenant improvement activities well ahead of the time allowed on the master construction schedule. The system focuses on asking each trade foreman (the last planner) to identify all activities that must be completed in a given work area in order for their work to proceed efficiently and to pre-plan their work. Using pull scheduling, the result was a network of commitments between subcontractors and Lewis that fostered teamwork and accountability to one another while working towards milestone activities in the master construction schedule. By ensuring that work was ready to proceed prior to starting an activity made for more efficient production, thus saving time and cost for the owner.
About Lease Crutcher Lewis
Lease Crutcher Lewis has been a leading Northwest general contractor since 1886, and has been based in Seattle since 1939. Lewis maintains a steady volume of work by being strong in numerous project types, including office buildings, renovations and tenant improvements. Common themes for its work include a team approach to working with our customers and design partners, a focus on innovation, and performing a large percentage of its work with its own craftspeople.