Factory-Built Houses; What, Where and How?
As the race to 3D print houses at large scales continues to gain momentum, companies come up with unique ways to stay ahead of the game.
As evident by the name, factory-built houses are housing structures fabricated in factories which are later shipped to site.
Mighty Buildings is a construction technology company based in Oakland, California who has been working to deliver factory-built homes for customers. Their construction process involves 3D printing, robotics, and automation and Mighty Building claims to be able to print a 350 square feet house in 24 hours, although the whole process including unit selection, site assessment, entitlement service, permitting process, and delivery, could take months.
They offer sizes ranging from 350 square feet to 1440 square feet.
Mighty Building is only delivering houses within California at the moment, with the hopes of expanding to the whole country and eventually the entire world. Other startups that may be focusing on pre-fabricated houses could grow elsewhere as long as safety standards and building codes are met.
The company is also working on a project taking place in Rancho Mirage, California. Their goal is to 3D print a community consisting of 15 homes, in an affordable and sustainable manner.
The current process involves the use of UV curable material, 3D printing, and robotics for manufacturing, although much of the entire process still requires manual labour.
Unlike conventional construction materials like concrete, Mighty Buildings uses a thermoset composite material which they call Light Stone Material (LSM). How this really helps with speed is that it can be cured when exposed to UV light, instead of waiting for the material to set and harden over time.
The material Mighty Buildings uses can be printed horizontally in the air without support which takes down the challenge of overhangs.
“One way to think about it is, you know when you go to the dentist, and they use the UV curable fillings and everything, if you take that and then you combine that material with mineral filler, you get… it’s basically a synthetic stone.” — Sam Ruben, CSO & Co-Founder.
Sam describes the extensive testing of the material and says its built to last.
However, the company is also reportedly experimenting with a new, fiber-reinforced version of the material that has similar strength characteristics to steel which will reduce material usage and allow for multi-story construction.
The 3D printer used for the project is a light-based printing system.
According to UL [Underwriter’s Laboratories], its the world’s largest light-based printing system. — Sam Ruben, CSO & Co-Founder
The printer is a gantry-style printer and is named “The Big G”. It shines Ultraviolet light onto the printing material and cures it almost instantly. It is supposedly able to print everything from panels to full, room-size volumetric modules.
The secondary post-processing system utilizes industrial robotic arms which are responsible for the exterior finishing such as trim the material, or go from a raw print to a smooth finish. This emphasizes the automation of the process, reducing manual labour and ensuring accuracy. Mighty Building is currently aiming for 80% automation of the process.
In the case of smaller houses, such as the 350 square feet unit, the unit is loaded onto a truck and delivered to the site, where it is carefully placed and all of the finishing processes are carried out.
For larger models, the company plans to ship the house in segments, which would be chemically sealed together on-site.
Mighty Building claims to be able to print a 350 square feet, single module home in 24 hours, which according to Sam Ruben is different than companies who also claim to be able to print houses in 24 houses.
“Often times, you’ll hear them say they can print in 24 hours or 48 hours but then you read the fine print and you read that it was done over a matter of days or weeks… We can print a 350 square foot module in less than 24 hours and that’s actually 24 hours, not 24 hours over a matter of days and weeks.”
Mighty Studio, which is the single module offered by Mighty Buildings, is sold for $115,000 for just the unit in California. The panel system which consists of 3 bedrooms and 2 bathrooms goes up to $285,000 just for the structure itself.
These prices seem to be higher than what other 3D housing printing companies seem to boast. Nonetheless, a much deeper analysis is required to calculate costs and efficiency, especially where demographics also seem to have a large influence.
While many skeptics fear 3D printing housing projects to become another decorative footnote of architectural history, companies like Mighty Buildings continue to develop their technology and look to expand into the construction market.
As the major industries in today’s age are moving towards automation, construction could be considered to be slightly lagging behind. More research and development is required in order for this technology to be considered as the primary method for construction which includes feasibility, and complex operation abilities.