KX-FOREST KARUIZAWA

Location

Karuizawa, Nagano
Japan

Project Size
5.06 acres
Project type
Institutional / Educational
Site Context
Suburban
Former Land Use
Previously Developed
Terrestrial Biome
Temperate deciduous forest
Project overview

KX-FOREST KARUIZAWA-Kajima’s corporate resort in Izuminosato, Karuizawa-, a wellness retreat located in Izuminosato, Karuizawa, is set on a company-owned site that preserves a rich natural environment. Villa-style accommodations are thoughtfully arranged to blend seamlessly with the surrounding landscape, creating a serene and high-quality resort space nestled within a tranquil forest.

In the development of this facility, significant efforts were made to preserve and utilize the site’s existing natural features, including greenery and water bodies, in a manner that fosters harmony with the local landscape and ecosystem. The project also integrated a variety of environmentally responsible measures, including circular economy practices such as the reuse of timber harvested on-site. These initiatives reflect the project’s strong commitment to environmental conservation.

The development process was characterized by a comprehensive approach to sustainable design, which included site-specific surveys to address challenges, followed by sustainable construction practices and ongoing operational management. The overarching strategy focused on sustainable development, ecosystem conservation, and reducing environmental impact. The following outlines the primary environmental features of the project.

Biodiversity Conservation
This project sought to preserve, create, and nurture environments that support the habitation and growth of a diverse range of plant and animal species.
Prior to the design phase, an on-site survey was conducted to assess the presence of endangered and rare plant species. Based on the findings, targeted conservation efforts, including protection and transplantation, were carried out. Additionally, surface soil containing native seed banks was preserved and reused during construction to support the regeneration of local plant species. Existing trees were retained wherever feasible, and new plantings were limited to indigenous species to ensure ecological continuity.

From a biodiversity conservation perspective, special attention was given to preserving and restoring the local aquatic ecosystem. A population of Luciola lateralis (Heike fireflies), a regionally significant species, was protected before construction began and reintroduced to the restored water features post-construction. Furthermore, artificial nesting habitats were installed for native species such as the Japanese giant flying squirrel (Petaurista leucogenys) and owls, contributing to the overall biodiversity. Post-project monitoring confirmed the return of these species, including sightings of the flying squirrel.

Efficient Resource Utilization and Climate Change Mitigation
As part of this project, timber harvested from the site during villa construction was repurposed for use in the landscape, villa construction materials. In addition to this, the project involved planting more trees than those that were removed, with a planting plan that aligns with the local climate and conditions. The landscape was designed to ensure that, after the initial establishment period, no irrigation would be required for plant maintenance.

Using the technology of 3D printing to shape the CO2-absorbing concrete "CO2-SUICOMⓇ," which Kajima Corporation is jointly researching with Kanazawa Institute of Technology, a pedestrian bridge was constructed on-site. Additionally, all excavated soil and stone were reused on-site, and rainwater is treated and managed within the property, contributing to a significant reduction in environmental impact.

Enhancement of Well-being and Environmental Education
The project integrates several initiatives aimed at enhancing the well-being of its users. Walking paths that leverage the site’s natural topography, alongside fitness programs such as yoga, are designed to promote physical health and mental wellness. Moreover, a nature-based environmental education program has been developed for visitors, including children, to engage with the site’s biodiversity in a safe and enjoyable manner. This program, led by environmental experts, fosters learning about the local flora and fauna, further connecting visitors to the natural environment.

In our journey to achieve SITES Platinum certification, Kajima Corporation partnered with Woonerf Inc., sustainability consulting firm with expertise in international green building certifications. In the future management and operation stages, we will continue to enhance and maintain a sustainable landscape through various monitoring efforts.

Certification level
Platinum