Audrey Woods, MIT CSAIL Alliances | September 28, 2026
MIT CSAIL Assistant Professor Mariana Popescu has a radical idea. What if we could use knitting to build complex architecture? Right now, constructing non-traditional building shapes requires wasteful and expensive molds and wooden frameworks, most of which gets thrown away after the project is complete. But what if knit fabrics—easy to make, cheap to ship, and better for the environment—could serve as flexible formworks? Popescu has proven this out with her various projects, which are adaptable, efficient, fast, even beautiful.
In the most recent episode of Building 32, Popescu explains how her research sits at the intersection of computational design, digital fabrication, and structural engineering. Learn about the potential impact of her work, the opportunity for such a novel approach, and the on-the-ground reality of her research by the numbers.
~40%: Share of worldwide greenhouse gas emissions linked to construction
Most people—including Building 32 host Karen Given before this conversation—don’t realize just how big of a carbon footprint the construction industry has. The UN Environment Programme's most recent Global Status Report for Buildings and Construction claims the sector accounts for 34% of global CO₂ emissions and consumes 32% of global energy. The World Green Building Council puts the combined figure at 39% of all global energy-related carbon emissions. This is an enormous societal and global cost. While we can’t just do away with construction, this means it’s in our collective best interest to find cheaper and more efficient ways to build, especially because…
2.1 billion: Additional people expected on Earth by 2050
"Whether we like it or not, we're going to have to build housing and infrastructure for them. And if we do things the way we do today, we're gonna be faced with more pollution, resource depletion and a whole lot of waste." — Mariana Popescu
This reality, according to one Nature study, means that the estimated carbon footprint of construction could double by 2050. Even if every other industry zeroed out its emissions, construction alone could consume the remaining carbon budget. These statistics give urgent importance to Popescu’s efforts. But how, in reality, does knit construction work?
38 kilos (~80 lbs): Total weight of Necto, the installation shown at the 2025 Venice Architecture Biennale
To showcase the lightness of the structure and the intelligence that can be embedded within a knit formwork, Popescu and her colleagues set up an installation at the 2025 Venice Architecture Biennale called Necto. The exhibition took place in a protected building, which meant the pillars and walls were "incredibly protected because there’s plaster that has been there for hundreds of years.” Because the entire Necto structure was only 38 kilos, or 80 pounds, they were allowed to hang it. “We're very lightweight, we could bring it in and also leave without a trace.” As an added bonus, the Necto fabric was entirely biodegradable.
Similarly, the fabric formwork for KnitCandela, a display built in Mexico City, was light enough that Popescu and her colleagues carried it in their suitcases when they flew to Mexico for the project.
750 hours vs. 40 hours: Time to produce 500 sq ft of formwork (traditional milling vs. industrial knitting)
The KnitCandela project also showcased how using knit formwork is significantly faster than traditional methods. Popescu’s knitting machine can produce mold for about fifty square meters, or 500 square feet, of construction in only 40 hours. Milling foam for the shape of something like KnitCandela would take an order of magnitude more time, up to three months, with waste compound on top of that. Traditional construction sites waste as much as 30% of all building materials delivered. For KnitCandela, Popescu says, “we went into the courtyard with a backpack and left a structure.” No waste, minimal extra materials, and a beautiful piece of art left behind.
Popescu does not imagine her knit formworks are going to replace everything, and she doesn’t predict that all buildings of the future will look like Necto. But she hopes her work will be “a stepping stone” to future construction ideas that will have a ripple effect on how things are made. There are other formwork options, other ways to think sustainably and creatively about architecture, that might adjust the numbers of construction to everyone’s advantage. She says, “The more we can design, understand, and manufacture these meta-materials, the more possibilities we have with them.”
Mariana Popescu is an Assistant Professor in MIT EECS with a shared appointment in the Department of Architecture. Listen to her full conversation on Building 32 wherever you get your podcasts.
