The Ice Box Challenge Consortium is delighted to announce that after making many stops around the globe, the Ice Box Challenge will land next in Sweden, from May 6 – June 6, 2025.

The #IceBoxChallenge is a prestigious international competition, held for the past 18 years in cities such as Vancouver, Los Angeles, Oslo, Melbourne, Santiago, Glasgow, and New York, attracting over two million visitors. This unique experiment showcases how homes can be designed to be energy-efficient, sustainable, low-carbon, and comfortable. During the challenge, ice boxes are placed in public spaces, and after a set period, the amount of ice remaining inside reveals how effectively each box resisted the summer heat. This demonstrates how better building design can reduce carbon emissions while ensuring homes remain comfortable, quiet, and healthy.

For the first time, Sweden will host the national competition in 2025, open to a maximum of five universities.

Are you an University?

APPLY TO PARTICIPATE BY SEPTEMBER 30TH, 2024

Pushing the Boundaries of Sustainable Design

Students of architecture and engineering are tasked with designing and constructing two ice boxes according to the competition’s guidelines. One box will adhere to Sweden’s BBR29 building code, while the other will feature a Passive House building envelope (PHPP), with full insulation, no thermal bridges, airtight construction, Passive House windows, and more. The design should also allow for easy assembly and disassembly, with a focus on materials that minimize climate impact (considering circularity, recyclability, climate declarations, and buildability). In spring 2025, the two ice boxes will be placed in a public location (TBA) for one month to test their performance.

GET INVOLVED

Hear directly from the students of the 2023 Pratt Institute Ice Box Challenge:

In spring 2023, the 4th-year architecture students at Pratt Institute explored Passive House. Their solution to the Ice Box Challenge both empowered them with knowledge and skills, as well as helped them become environmental and social agents of change as they contribute to their local, and greater communities. They learned by actively creating, innovating, and engaging themselves and others to learn through their public exhibition of the Ice Box Challenge.

The challenge was rganized with the great support of Passive House For Everyone! is the Education Arts arm of ChoShields Studio, a Certified Passive House architectural practice that offers extensive architectural and technical expertise with a strong multidisciplinary approach to strengthening communities through designing and building energy-efficient structures.

_{Click the image on the left to watch a short video of student testimonials}

What is the Ice Box Challenge?

The Ice Box Challenge is a public installation that visually demonstrates the benefits of energy-efficient buildings.

Two boxes are constructed—one to local building standards and the other to the international Passive House Standard. Both are filled with either 1m³ (917kg) or 1 metric tonne (1000kg) of ice and placed in a central, high-traffic area. After a set period, the remaining ice in each box is measured to show how well each one insulated against heat.

This challenge makes the often invisible concept of energy efficiency tangible and engaging. Passive House buildings, with their significantly lower energy demands, play a crucial role in climate protection.

WHAT IS A PASSIVE HOUSE?