A geometrically complex tower rises in Boston, featuring high-performing double-height unitized curtainwall.

The 18-story Block L4 mixed-use development is WS Development’s newest addition to its emerging Seaport Square masterplan. As envisioned by Gensler, the stacked, twisting volumes give the massing a dynamic appearance, creating large open-air terraces for each floor of the tower. 

Island worked closely with all stakeholders during the design assist phase to craft a bespoke enclosure system that is tuned to the design goals of multi-story curtainwall spans while accommodating installation logistics of the triple-glazed system. At the double-height “setback” portions of the facade, a customized single-story version of the curtainwall chassis was deployed, enabling installation in areas inaccessible by crane. To deliver on the design intent of clean, streamlined surfaces throughout, Island engineered these unitized interfaces to minimize visible joints across the facade.

Following onsite mockups to select final material vendors and subsequent performance analysis by a third-party testing agency, the complete facade system was fabricated at Island’s New York facility. 

Both the floor-set “typical” curtainwall and crane-set “large-format” units were held to stringent tolerances and QC procedures prior to shipment to site, where they were installed with a superstructure crane and glazing manipulators. 

Project Information:

• Year Completed: 2021

• Certification: LEED Gold

• Facade Area: 164,802 SF

• Panel Count: 1,659

• Island Services Provided:

  • Design Assist

  • Engineering

  • Fabrication

  • Installation

Learn More:

• Gensler, 111 Harbor Way | Projects | Gensler

• BPDA, Seaport Square Block L4 | Boston Planning & Development Agency (bostonplans.org)

• Boston Business Journal, Here’s a first look inside Amazon’s new Seaport building