Joan Gibbons realized she’d made a huge mistake: She’d forgotten to label the roof beams of her prototype solar house, and now they were all in a huge, mismatched and unorganized stack.

Gibbons, a UC Berkeley senior studying civil and environmental engineering, was the organizational brains behind the university’s entry into the Department of Energy’s Solar Decathlon, a collegiate competition to design and build full-size, solar-powered houses.

A group of nearly 40 Berkeley students spent two years designing, funding and building their entry, a stackable one-story house that they hoped would eventually end up in Richmond. Earlier this month, they were awarded third place by a panel of judges who ranked the team in 10 different areas including architecture, marketing and energy use.

But in July, the team was behind schedule – permitting had taken longer than expected – and the roof beams were a mess.

“We had a drawing and a stack of wood and we had to figure out,” Gibbons, 22, said. “It was a big challenge to manage people and interpret drawings and figure out when we needed to step back and figure out what we we’re doing, the big picture; that was the hardest part.”

A lot of joist hangers ended up in the wrong place, but eventually the team figured it out. Gibbons, who is thinking of pursing a career in construction management when she graduates, said she learned something that day she’d never fully understood when she read it in a textbook.

“Organization is really key on a construction project,” she said with a knowing laugh.

The student-led team was started two years ago by Sam Durkin, 22, and Brenton Kreiger, 22, who have since graduated. The group designed a fully code-compliant one-story house, submitted the plans for review, raised some $230,000 in donations of time, money and material and built the house in Denver, where this year’s competition was held.

The modular house was stackable up to three stories and featured moving walls and a folding bed that would give a family room to entertain friends or create a separate space for a guest. The north outside wall was covered in moss to “sequester carbon and clean the air,” according to the team’s proposal.

“We built everything ourselves, besides the fire sprinkler system; we paid somebody to do that,” said Ruth McGee, 21, a senior civil and environmental engineering major and one of the project’s student leaders. “We hired an electrician and plumber to advise us on the mistakes we made.”

“I felt like it was a whole different kind of education,” McGee added. “I have my technical education at Berkeley, and my practical education came this summer while problem solving and figuring things out.”

The team, which was a joint effort between Berkeley and University of Denver students, was given top honors by the judges for their engineering accomplishments. The team was ranked first for effective appliance use, and second for energy use, health and comfort and home life.

Of the 17 teams that entered the competition, only 11 were actually able to build functional homes at the competition space in Denver.

“In general our mission was just to get a house to the competition,” McGee said. “Just getting a house built, we can be proud of that.”

While the group had originally hoped to bring the house to Richmond, it will stay in Denver and be offered to a low-income family, which is a testament to homes design and functionality.

“We kept saying the whole time: ‘We want someone to live in this,’” McGee said. “That was really important to us. Would a person living in this house want to have this?”

Contact Will Kane at willkane@berkeley.edu