Architectural firm Wiencek + Associates envisions a phone app that can fight world hunger. But since it is in the business of designing local residential properties and senior living facilities — not phone apps — they figured out how to build an iPhone structure out of canned food instead.

It was one of the 20 structures that design, engineering and construction companies built as they competed in this year’s CANstruction event at the National Building Museum, hosted by the Washington Architectural Foundation.

Architectural firm Leo A. Daly built a Capital Bikeshare bicycle — the juror’s favorite. Einhorn Yaffee Prescott built a Smurf village using cans for tree trunks and David M. Schwarz Architects constructed a food truck incorporating lifesize cutouts of the Obama family and an awning made from taco seasoning packets. That won best meal.

Teams had been designing their structures since early summer but had only six hours to build their designs, which were left on display for a week and then donated the cans to the Capital Area Food Bank.

“It was like having a second job,” said Matthew Lee, architect at Wiencek and CANstruction team captain. The company spent $4,500 to purchase materials and 3,200 cans. Before mocking up a digital design, Lee and his team found themselves at their local Giant wrapping measuring string around cans of Giorgio mushrooms and snapping photos to ensure they were the perfect fit for their iPhone design. The team won an honorable mention.

The event collected 47,000 cans and more than $4,000 in donations, which the food bank translates to a total of nearly 49,000 meals.

“They gave more weight than what you would see in a tractor trailer traveling on the highway,” said Michael Gillespie, food resources director at the Capital Area Food Bank.

Visitors used cans to vote for their favorite, crowning GPI/Greenman-Pedersen’s airport security scanner scene, called “Hunger is sCANdalous,” with the People’s Choice award.

Other companies included AECOM, URS, SmithGroupJJR and Robert Silman Associates. The event’s sponsors were Builders’ Ball, Giant Food, Hilldrup Companies, National Building Museum, NRI, TW Perry.