Don’t throw stones at this glass house. Researchers have now developed a new method to 3D print recycled glass into durable, reusable building bricks, potentially reducing buildings’ embodied carbon.

Urban Tech: The engineers presented three brick manufacturing methods: fully hollow without interlocking, print-cast, and fully printed with interlocking components in a study published in the journal Glass Structures and Engineering.

“Glass is a highly recyclable material,” Kaitlyn Becker, assistant professor of mechanical engineering at MIT, said in a statement. 

“We’re taking glass and turning it into masonry that, at the end of a structure’s life, can be disassembled and reassembled into a new structure, or can be stuck back into the printer and turned into a completely different shape. All this builds into our idea of a sustainable, circular building material.”

• Circular construction aims to reuse and repurpose a building’s materials.

• According to the U.S. Environmental Protection Agency (EPA), manufacturing construction materials makes up about 15% of global greenhouse gas emissions.

Durability, Reusability & Sustainability 

The engineers tested the durability of these glass bricks using a hydraulic press. They discovered that bricks made primarily from printed glass with separate interlocking features on the bottom were the most durable, withstanding pressures comparable to concrete blocks.

“We have more understanding of what the material’s limits are, and how to scale,” said Michael Stern, former MIT graduate student and founder of Evenline. 

“We’re thinking of stepping stones to buildings, and want to start with something like a pavilion — a temporary structure that humans can interact with, and that you could then reconfigure into a second design. And you could imagine that these blocks could go through a lot of lives.”