A skybridge connecting two office buildings under construction in Boston's Seaport district doesn't seem out of the ordinary at first glance. But the 99-foot-long, climate-controlled, pedestrian-only bridge was not designed to stay put.
The bridge at Vertex Pharmaceuticals’ corporate campus is an example of an emerging architectural concept: designing buildings and structures to be easily and cheaply removed or renovated when they no longer serve their original purpose. It's a theory sometimes called Design for Disassembly.
There is an urgent need for the design concept, as the construction industry is a notoriously voracious consumer of raw materials. If general contractors can use recycled materials instead of buying everything new, it can extend the life of the planet's limited supply of natural resources, according to the Global Cement and Concrete Association.
The use of recycled building materials can also help prevent landfills from overflowing with construction debris, according to the Department of Planning and Sustainability in Portland, Oregon. Portland was the first U.S. city to require the recycling of building materials during the demolition of certain residential buildings.
Those reasons influenced the SGA design team's decision to use deconstruction techniques for the Vertex skybridge in Boston. Even if the skybridge is removed, its parts and materials can still be used later in other buildings.
“We’re trying to extend the useful life of anything we are designing,” Joe Mamayek, an architect and principal at SGA who designed the Vertex skybridge, told CoStar News.
The skybridge spans Northern Avenue to connect two Vertex buildings that house the pharmaceutical developer’s cell and genetic therapies research and clinical manufacturing. The 247,000-square-foot Jeffrey Leiden Center I building opened in 2020. The second building, called Leiden Center II, and the skybridge are still under construction and expected to open this year. Vertex, SGA and lead developer Related Beal haven't disclosed the estimated cost of the skybridge.
Mamayek’s design for the 160,000-pound Vertex skybridge required atypical steps to ensure it could be easily removed at some point. The bridge was largely assembled off-site and trucked to the construction zone. The glass walls and roof of the skybridge, along with underside metal panels, can be removed and adapted for use as a bridge at another project, or the parts could be disassembled and used individually for something other than a bridge.
Lost value
About 95% of construction materials' value is lost as buildings age, become obsolete and are later demolished, according to Arup, a London-based design and engineering firm that advises designers and builders on sustainable construction techniques. Buildings that include materials and components that can be recycled retain more value over time. That's because the building owner can sell those parts if they're ever disassembled.
The renewable building concept has been around for at least two decades, but it hasn’t yet latched on with major industry players, SGA's Mamayek said. One big reason is the lack of industry-approved standards for assessing the quality of building materials that have already been used in a structure.
Despite the perceived higher costs of Design for Disassembly, some commercial developers have said they’re willing to absorb higher costs at the outset of a project if there is potential for a building to hold value for a longer time, according to a December 2024 report by the Massachusetts Institute of Technology’s Climate and Sustainability Consortium.
But the industry hasn’t even settled on a single name for the concept. Among the many names that have been used are Design for Disassembly, Circular Buildings, Reversible Architecture, Planned Obsolescence and Regenerative Design.
The theory also lacks a uniform set of procedures for designing for eventual removal or recycling. Mamayek wants to get the ball rolling on that front with his design of the Vertex skybridge. He’s compiling extensive data and an inventory of materials that can be accessed with a digital passport to assist future owners who may need to remove the structure.
“It’s going to make it much more transparent to help understand what’s there,” Mamayek told CoStar News.
A pedestrian skyway is an ideal test subject for the concept because it’s easy to visualize a future scenario where it’s no longer needed, he said. Crucial to Mamayek’s theory is that the Vertex skybridge design won’t damage either building if it’s removed at some point.
“If someone is going to eventually do a careful removal and reuse of the skybridge, it has to be designed in a very particular way,” Mamayek said. “It’s not just demolishing it and salvaging the used steel and concrete.”
Embracing the concept
Some design and construction professionals who are embracing Design for Disassembly have discovered a few best practices.
Connection points where two or more building components are attached, for example, should use mechanical means rather than chemical ones, according to Andreea Cutieru, a Romanian architect who has studied Design for Disassembly. For potential disassembly, bolts, screws and nails are superior materials to chemical sealants and binders, glue and welding, Cutieru wrote in a report for trade publication ArchDaily.
Completed projects that used Design for Disassembly include the arena where handball events were held during the 2016 Summer Olympics in Rio de Janeiro. The arena was designed with modular components that were later used to build four schools in the city, according to trade publication Archello.
Other projects have used bits and pieces of Design for Disassembly methods. Arup designed a property in California in 2021 for Google to consolidate its Real Estate & Workplace Services division from several warehouses into one centralized location. The project recycled office furniture and equipment from other Google locations and diverted about 1,200 pounds of material from landfills, Arup said.
Mamayek admits that the Design for Disassembly concept is somewhat counterintuitive to how architects think — wanting their work to live forever. But the traditional mindset took hold during a period when recycling and climate change were virtually unknown topics. Times have changed, he said.
“We design things with the hope that they will have incredible lifespans,” Mamayek said. “But sometimes that doesn’t happen.”
For the record
SGA and Dream Collaborative are the design architects for the Leiden Center II building. Boston Real Estate Inclusion Fund, Basis Investment Group and Kavanagh Advisory Group are co-developers in partnership with Related Beal. Consigli Construction is the general contractor. McNamara Salvia is the structural engineer.