Top-Down Construction, Innovation for Cost, Schedule, and Safety Benefits

Top-down construction is an innovative and financially attractive solution that has proven to be successful for new building projects under specific site constraints. In this session, the Manhattanville Campus of Columbia University, for which WSP served as the structural engineer, is used as a case study to illustrate the main concepts behind top-down construction and how it contrasts with conventional construction methods.

The course highlights the conditions where this construction method is likely to be used, namely, congested construction sites or staging areas, presence of high groundwater, and adjacency to existing buildings and infrastructure projects. The case study shows how top-down construction was used not only to streamline the construction of the Manhattanville Campus by significantly reducing its duration, and thus, saving time and money; but also allowing for innovative structural solutions such as the dual-purpose of temporary supports later used as permanent structural elements.

This session will:

• Cover the benefits of top-down construction, including safety-related aspects during construction and use.
• Outline how the top-down approach is a schedule and cost-saving technique, as well as positive impacts on the safety and welfare of occupants during construction and use.
• Discuss relevant design considerations for phased construction.
• Identify the importance of construction sequence in an urban setting to address specific challenges while addressing health and safety concerns.