Citygreen / Case StudiesAmazon leverages cutting-edge Stratacell solution in new Seattle headquarters

Amazon leverages cutting-edge Stratacell...

Amazon leverages cutting-edge Stratacell solution in new Seattle headquarters



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E-commerce and cloud computing company, Amazon, has leveraged Citygreen’s cutting-edge Stratacell™ system in its new multi-million office headquarters in South Lake Union, Seattle. Purpose-built to accommodate 20,000 employees, the new headquarters consists of multiple buildings surrounded by mingling areas and plazas.

One plaza, located between two buildings on 6th Avenue, has been constructed above a parking structure, and is home to several feature trees (Cercidiphyllum japonicum and Magnolia laevifolia) requiring large planting areas.

Amazon leverages-cutting edge Stratacell solution

Engineering plans allowed enough soil volume beneath the plaza to house the trees, but a significant challenge emerged – how to provide sufficient structural support to cope with the weight of heavy vehicles such as a boom lift, to be used for maintenance. Soil cells were identified as an ideal solution, however many products were rejected because they lacked the structural strength required.

Stratacell in Amazon new Seattle headquarters

Citygreen’s 60-series Stratacell system fulfilled the strength requirements, and Citygreen worked directly with the consulting landscape architect – Site Workshop of Seattle – to design the structural elements of the plaza. This consists of 500 StrataCells, supported by a concrete slab, a drain-mat, and another slab above. Citygreen provided plan views of the installation to calculate the quantity of cells required, and to show how the slab would be supported. Construction was completed by Pacific Earthworks.

Amazon leverages cutting edge Stratacell solution

November 2015


July 2019


Site Workshop, along with the project architect, are very happy with the solution, making particular note of how quickly the cells went together and how easy it was to thread the drip irrigation through the structure. Time will tell how the rigidity of the plaza structure performs, but all signs point towards to successful outcome, with beautiful trees for Amazon employees to enjoy.