Earthboat by Pan- Projects: Revitalising Japan’s Underused Landscapes

Japan’s natural beauty is vast and varied, yet many leisure spaces—once thriving with activity—now sit abandoned due to shifting demographics and societal changes. Earthboat, a mobile, lightweight accommodation concept by Pan- Projects, emerges as a strategic response to this challenge.

Designed to rejuvenate underutilised locations such as disused ski resorts, neglected fishing ponds, and forgotten forest grounds, Earthboat offers a low-impact yet engaging way for people to reconnect with nature. By integrating elements like sauna experiences and minimalistic, sustainable design, Earthboat transforms overlooked spaces into destinations, ensuring that their revival remains adaptable and ecologically responsible.

See also our interactive map of prefab projects

photography by earthboat, published with bowerbird

What inspired the creation of Earthboat, and how does it address the challenge of revitalizing underused leisure spaces in Japan?

Earthboat was born from a simple yet powerful idea—to create a space where people can coexist with and fully enjoy nature. While Japan is home to diverse natural landscapes, Earthboat specifically seeks to revitalise abandoned ski resorts, forest sports grounds, fishing ponds, and neglected traditional rural landscape areas that have fallen into disuse due to population decline and societal changes.

By introducing Earthboat to these underutilised spaces, people naturally begin to spend time there again, breathing new life into the landscape. This not only helps restore and maintain these forgotten areas but also ensures that if, in the distant future, the accommodation facilities are no longer needed, they can be removed without leaving a permanent footprint, allowing the rejuvenated natural environment to remain intact.

Attracting people to remote locations with no existing entertainment can be challenging. However, Earthboat incorporates a sauna experience, creating a unique draw where the combination of nature and sauna is enough to bring people together, transforming overlooked spaces into vibrant destinations.

Earthboat is designed without fixed foundations, allowing it to “float” above the ground. What were the biggest design and engineering challenges in making this concept a reality?

Earthboat is not classified as a “building” under Japanese law because it does not have a fixed foundation, meaning it is not subject to the Building Standards Act. However, this also meant that we had to design it within a new set of regulations that differed from those for vehicles and trailers, which presented a unique challenge.

One of the most significant structural challenges was ensuring stability without a fixed foundation.

Even in conventional architecture, foundations can experience uplift forces. For example, in high-rise “pencil buildings,” certain foundation parts may lift during earthquakes, which is why deep piles anchor them to the ground. Similarly, in reinforced concrete (RC) houses, which are highly rigid structures, smaller-scale foundations can also experience partial uplift. In such cases, structural stability is ensured by reinforcing the foundation beams and considering the restoring force generated by the building’s self-weight.

Earthboat follows the same structural principles.

Its rigid CLT-panel structure experiences some uplift forces during an earthquake, but the high stiffness of CLT mitigates this effect. Additionally, its self-weight provides restoring force, preventing it from toppling. The jacks placed beneath the structure also remain stable, as the friction between them and the ground is greater than the horizontal seismic forces acting on them, preventing displacement. Furthermore, the wide base of the column supports reduces the risk of overturning.

Cross-Laminated Timber (CLT) is typically used for large-scale construction in Japan. How does Earthboat demonstrate its potential for small-scale, mobile architecture? 

Through the Earthboat project, we have identified key challenges hindering the widespread adoption of CLT in Japan. The primary obstacles include unstable demand, leading to production limitations and a shortage of skilled CLT builders. To address these industry-wide issues, Earthboat has worked closely with CLT manufacturers, engaging in continuous improvements and refinements. Additionally, as a long-term initiative, Earthboat provides manufacturers with a stable and predictable demand for CLT production.

Practically, this involves a feedback loop where each unit’s construction process informs the next design iteration, improving manufacturability while also securing a steady workflow for CLT processors. This, in turn, enhances processing efficiency, equipment investment, and workforce skill development. For builders, Earthboat serves as an entry point into CLT construction, offering hands-on experience that contributes to cultivating a new generation of skilled CLT professionals.

This project is a small building of less than 25m², but it uses about 18 cubic meters of CLT, and we aim to produce 200 buildings per year in the future. Although the scale of each building is small, we aim to make a significant contribution to the spread of CLT materials and the transmission of CLT technology through this large-scale development.

With 60 units currently deployed across seven locations, what factors determine where an Earthboat cabin is placed, and how do you envision its expansion in the future? 

Earthboat prioritises immersive experiences in nature, selecting locations that offer breathtaking views, waterfront settings, and secluded landscapes where guests can fully engage with their surroundings.
Looking ahead, we aim to expand to 20 locations across Japan, focusing primarily on the Tokyo metropolitan area and its surroundings, where demand is highest.

Sustainability is at the core of Earthboat’s design. Beyond CLT, what other eco-friendly materials or practices have been incorporated into the project? 

Rather than incorporating a variety of eco-friendly materials, Earthboat’s defining characteristic is that it is constructed almost entirely from CLT. This project maximises the benefits of CLT, including its efficient construction process, excellent thermal mass and insulation properties, and natural aesthetic appeal while minimising the need for additional materials.

The interior is left exposed, meaning the structural and finishing materials are one and the same. Additionally, no insulation materials are used, relying solely on the natural insulating properties of wood to ensure indoor comfort. This minimalist approach to material selection is what makes Earthboat an example of sustainable architecture in its purest form.

How do guests respond to the Earthboat experience, and what role do you think projects like this play in shaping the future of eco-conscious travel and architecture in Japan?

Traditional accommodation options often present a trade-off: camping offers an immersive nature experience but lacks comfort, while conventional hotels provide comfort but feel disconnected from nature. Earthboat bridges this gap by offering a comfortable sleeping space in the heart of nature while enabling guests to enjoy activities like saunas and outdoor cooking, making nature accessible without compromise.

Japan has vast natural landscapes, yet many areas remain underutilised due to construction challenges. Because Earthboat has better mobility than traditional buildings, it can be placed in locations previously deemed unsuitable for development, opening up new opportunities for people to experience these overlooked environments.

Moreover, Earthboat reinforces a fundamental idea—the richness of a stay is not defined by the size of a space or its luxury but by the beauty and presence of the surrounding nature. By shifting perspectives on what makes an accommodation truly valuable, Earthboat contributes to shaping the future of eco-conscious travel and architecture in Japan.

Author: admin