Ice Box Challenge comes to Sweden - students from Luleå University of Technology compete in sustainable construction

How do you prove that sustainable construction actually makes a difference? Through an ice-cold experiment! The Ice Box Challenge is a global competition that has been organized in over 17 cities for the past 18 years - and now it has come to Sweden.

For the first time, students from five Swedish Universities and colleges are taking part in the challenge to design and build the most energy-efficient mini-houses. The competition is as simple as it is ingenious: two identical boxes are built, one according to conventional building standards and one according to Passive House standards. Both are filled with ice and left outside for several weeks. When the time is up, the amount of ice left in each box is measured - a clear demonstration of the difference in insulation and energy efficiency.

Two teams of engineering students from Luleå University of Technology are ready to take on the challenge. We talked to them about the competition, their design ideas and what they hope to achieve.

"We want to inspire sustainable building"

Valentin Romero, Project Manager Sub-Zero Studio:
"We are nine students, all studying architecture and we are from three different years. It's a logistical challenge to meet sometimes, but we have the advantage that people have done different things and come with different perspectives and interests. Our name comes from the competition itself that we are building an icebox, but we wanted something that didn't sound like an architectural office, but more like do-it-yourselfers in civil engineering, architecture, design and sustainability."

What are you looking forward to most about the competition?
"It's hard to speak for nine people, but for me it's always been a dream to design something and see it stand up somewhere in reality and be able to influence other people. This gives us an opportunity to influence other people's thoughts and inspire sustainable building. We have networked a lot and we are met by so many positive tones. It also gives an extra motivation and positive feeling to the project."

What do you think will be the biggest challenge during the design process?
"I guess it's not getting caught up in details. The design is important, but we have not done this before. Now we are designing in the smallest detail and you have to find out a lot of things that you don't know anything about before. It's a big challenge and you can get nervous that you'll miss something. Then of course to build everything. None of us are carpenters so we have to learn from scratch. We look forward to it."

What do you hope the competition will provide insights into sustainable construction?
"One insight we have already learned is that there is a lot in the vicinity of Luleå, that sustainable construction is not far away. It has been a great realization that there is a lot here in Norrbotten, many different stakeholders ready to help.

"It's great fun to apply the theory we have learned in practice"

Nelly Cedergren, project manager Frozen Frameworks:
"We are six architecture students, five from the fourth year and one from the third year. We wanted our name to make you think of Norrbotten, Luleå and put us on the map. We also build constructions so Framework felt natural."

What are you looking forward to most about the competition?
"It will be great fun to build the little mini houses and to apply the theoretical things we have learned in practice, to create something and see if our calculations hold. And to create something valuable and sustainable."

What do you think will be the biggest challenge during the design process?
"We are sitting with the design now and the construction solution is the difficult thing, to get the ice in a good way without releasing too much heat through thermal bridges. Then it will be a challenge to practically build the houses, which we have not done before."

What insights do you hope the competition will provide into sustainable construction?
"It will be interesting to see how big the difference is between ordinary houses and passive houses in practice. We can do the math and see that it has better U-values and is more energy efficient. But what does it really mean? I also think that it is not only us who gain insights, but the public as well. We can encourage people and create interest and curiosity in building more sustainably."