New Purdue lab provides tiny home for sustainability education
By Aaron Martin
At just 192 square feet, Purdue University’s newest civil engineering laboratory is remarkably small for a research space. Yet, Purdue professor Nusrat Jung has big plans for it.
The laboratory comes in the form of a tiny house, called zEDGE, that Jung and a team of students designed and engineered for testing the energy efficiency of large structures on a small scale. Built on a trailer for easy mobility, zEDGE (pronounced “zee-edge”) is stationed outside Hampton Hall on Purdue’s West Lafayette campus.
Jung envisions zEDGE, which stands for zero-Energy Design Guidance for Engineers, as an ideal working laboratory — and much more.
“It’s very small but it’s a powerhouse. zEDGE is a great research lab for our students, because it’s something very compact that still has all the energy efficiency parameters of a larger building, something very real that they can evaluate in real life,” says Jung, a visiting assistant professor in Purdue’s Lyles School of Civil Engineering.
“Beyond that, I think zEDGE is one small part of a step forward for energy sustainability in general,” she says. “In the U.S., we are really beginning to think about energy sustainability and our negative impact on the climate. As engineers, we need to be open-minded about the future and accommodate how the next generation will live. I think this is a prototype for future homes.”
Increased energy efficiency and small homes are not new concepts, and the two have been closely tied since the small house movement emerged in the 1980s. The movement calls for a return to houses of less than 1,000 square feet, with tiny houses typically defined as those that measure less than 400 square feet. By comparison, the average size of a single-family home in America has grown to more than 2,600 square feet.
What makes the zEDGE project innovative is its mission: Learning how to construct a truly zero-energy structure, which is the ultimate goal of many small-house and sustainability advocates. A zero-energy building has zero net energy consumption over a 12-month period, meaning the amount of energy it uses in a year equals the amount of renewable energy created on the site.
“Energy efficiency and sustainability are things that have always resonated with engineers and architects,” Jung says. “Now, more and more people are realizing how important it is. What I found out is that there is a lot of interest in zero-energy buildings, which is my area of expertise, but not much knowledge of how to build one.”
Fun with fundamentals
Jung began developing a plan to amass that knowledge and share it with students almost immediately after she arrived at Purdue in January 2019 and secured funding for a new teaching lab. She decided to encourage “fun with fundamentals, for the students, by building a zero-energy tiny house on wheels that we can take anywhere and do experiments.”
Jung recruited four students to join her design and engineering team, including graduate students Motasem Qadan, Aditya Shivaji Mane and Chengbo Du, as well as undergraduate student Reno Lewis Sarussi. The students worked on every aspect of the design, from modeling and materials to energy-use calculations and the electrical and plumbing systems — all with an eye on innovation, efficiency and sustainability.
The final design featured many new energy technologies and components, including cutting-edge measuring instrumentation, high-efficiency lighting, two types high-efficiency insulation and unique Zip System sheathing that created a totally enclosed “building envelope.” The house also has a solar energy system, pitched at the ideal angle for energy collection, and a water-collection system.
“There were definitely some advantages and some disadvantages to designing a tiny house,” says Qadan, who received his master’s degree from Purdue in December 2019 and now works at Advanced Engineering Consultants in Fishers, Indiana.
“The fact is that, with a tiny house, you can get away with some things that would take much more effort with a regular house — things like changing the direction of the house to reach the maximum solar energy potential. It is also easier to evaluate all the systems,” Qadan says. “But you have to give a lot of attention to detail on a house on wheels, one that could be driving down the highway at 80 miles per hour. Nothing was done at random.”
Finding the right builder for the project was one of the team’s toughest challenges, Jung says. After an extensive search, they partnered with Colorado-based MitchCraft Tiny Homes. Construction began last December, and the final product was delivered to Purdue’s campus in August.
“A lot of companies advertise that they can build you a custom home, but we were looking for very specific things — you’re dealing with engineers here,” Jung says. “MitchCraft was the only builder who could build it exactly how we wanted it.”
MitchCraft owner Mitch Holmes, whose company has been building tiny homes since 2015, found the project both challenging and rewarding.
“Each home we build is a completely unique project with its own set of processes and challenges, so the Purdue project was no different in that regard,” Holmes says. “But having Purdue engineers design the entire house, and having to build to such detailed specs, was definitely something new. It’s certainly a nice project to add to our repertoire.”
Eye on the future
While building a fun but practical teaching lab was the primary material goal of the zEDGE project, the members of the Purdue team had sustainability and future populations in mind while completing it. All four students were selected from a zero-energy building course Jung taught during her first semester at the University.
“Just knowing that this could be something for the future definitely left an impact on all of us,” Qadan says. “This isn’t everybody’s future, but it’s part of it. It’s about small steps, small changes, small things. You find yourself thinking, ‘This could solve a lot of issues, this could be a game-changer, this could help save the planet.’ ”
This was the first collegiate research project for Sarussi, a junior from La Grange, Illinois. He had a personal interest in sustainability before he arrived at Purdue, but working on zEDGE gave him his first formal exposure to it. Sarussi says the experience sharpened his focus.
“This allowed me to take something I found interesting and apply it toward a civil engineering degree,” Sarussi says. “In my first year at Purdue, I wasn’t sure if I wanted to study environmental engineering to civil engineering. This helped me discover that the environmental element and sustainability is key in civil engineering, too.”
In many ways, Jung sees both herself and zEDGE as part of a changing civil engineering landscape. Not only is she taking the lead as her field addresses the world’s emerging sustainability issues, she is a female professor in a traditionally male-dominated area.
“Stereotypes exist, of course, but I think the gender dynamic is changing,” Jung says. “One thing I really believe is that knowledge does not have a gender. I suppose I’m an example for young people of all genders that you can do amazing things if you simply have a passion. I think you can make your own story.”
Jung recently received a Protect Purdue Innovations Faculty Grant and will carry out a research project in zEDGE to evaluate the chemical risk assessment of COVID-19 disinfection activities in buildings.