The construction industry is currently caught between two mounting pressures: a global housing shortage and the environmental toll of traditional materials. While timber remains the standard for residential framing, the demand for wood is increasingly at odds with forest conservation goals. At MIT, a team of engineers is proposing a pivot toward a material usually viewed as a pollutant: single-use plastic.
Led by Professor David Hardt and research scientist AJ Perez, the team has developed a method for 3D-printing construction-grade beams and trusses using recycled PET polymers reinforced with glass fibers. Unlike existing large-scale additive manufacturing projects that print walls using carbon-heavy concrete or clay, this approach focuses on the structural "skeleton" of a building. The printed trusses mirror the diagonal, ladder-like patterns of traditional wooden floor supports, but with a significantly lower carbon footprint.
In laboratory tests, the results were more than theoretical. Using a room-sized 3D printer, the researchers produced four long trusses and integrated them into a standard plywood-topped floor frame. The assembly demonstrated a load-bearing capacity exceeding 4,000 pounds, comfortably surpassing the requirements for residential construction. By transforming plastic waste into a structural asset, the project suggests a future where the circular economy and the housing market are no longer at odds.
With reporting from MIT Technology Review.
Source · MIT Technology Review
