Amsterdam-based Monumental has closed a US$32 million Series B round led by Khosla Ventures, with existing backers Hummingbird and Plural also participating. The autonomous construction tech firm builds fleets of electric, AI-guided robots that lay brick and mortar on real job sites, and the fresh capital will fund a hardware expansion, grow its engineering team, and prepare its launch into the US market.
Rebuilding an Industry Stuck in the Past
Construction remains one of the last major global industries largely untouched by modern automation. While US manufacturing productivity has risen more than eightfold since 1945, construction productivity has actually declined since the 1960s, even though the sector still represents roughly 13% of global GDP.
That stagnation has real consequences: a worsening housing crisis driven by rising costs and an acute labour shortage. Monumental estimates the US alone is short between 200,000 and 400,000 construction workers every month, meaning homebuilders will need to recruit 2.2 million more people over the next three years just to keep pace with demand.
"The world simply does not have enough people to build what it needs. Every robot we deploy expands the industry's capacity to build, bringing a future of beautiful, affordable, bespoke buildings and infrastructure closer to reality."— Salar al Khafaji, Co-Founder and CEO, Monumental
How the Technology Works
Monumental's fleet of agile, electric autonomous ground vehicles is equipped with computer vision, advanced sensors and robotic arms. Rather than requiring manual control, the entire operation is orchestrated by Atrium, the company's proprietary AI software, which acts as a kind of digital foreman, translating architectural blueprints directly into precise coordinates so robots can lay brick and mortar with millimetre accuracy.
The machines are built compact enough to navigate tight, unpredictable spaces on active job sites. Monumental operates as an autonomous subcontractor, letting builders hire the machines — worth up to US$100,000 each — the same way they would hire any other trade crew, with the company delivering the robots, executing the build, and billing per square metre of finished wall. It has already built the walls for over 100 homes, a school, a hotel, a community hub, and canal barriers across the Netherlands and the UK.