Lib Earth House Model B: A 3D-Printed Earth Home Leading Sustainable Residential Innovation in Japan

Located in Yamaga, Japan, the Lib Earth House model B represents a pioneering step toward regenerative housing and circular construction. Designed by Lib Work Co., Ltd., Arup, ogawaa design studio, and Studio QTN, the project explores how 3D-printed earthen architecture and traditional Japanese timber craft can coexist to shape the future of sustainable living. Completed in 2025, this 132 m² single-story prototype embodies a new architectural vision where architecture, ecology, and advanced construction technology converge.

This second prototype in the Lib Earth House initiative redefines contemporary housing through biodegradable materials, circular construction systems, and habitat-driven design, addressing Japan’s rural revitalization and sustainable living aspirations.

A New Model for Earth-Based, 3D-Printed Housing

The Lib Earth House model B advances the project’s mission to develop fully biodegradable housing systems using region-sourced earth and natural binders. The structure relies on construction-scale 3D printing, forming thick earthen walls that promote thermal stability, hygroscopic comfort, and a connection to nature.

The walls are crafted from soil, lime, and plant-based binders refined through rigorous testing to balance:

• Structural strength and seismic performance
• Moisture control and crack resistance
• Workability and printing consistency
• Texture and visual expression

This commitment to natural materials supports a closed-loop construction lifecycle, where buildings return to the earth without environmental impact.

Hybrid Craftsmanship: Timber Structure Meets Earth Printing

While the walls are 3D-printed, the post-and-beam Japanese timber frame introduces a culturally rooted structural logic. Select steel connectors ensure precise integration, yet the earthen components remain structurally independent and self-supporting—a crucial step in validating earthen printing in seismic Japan.

Curved and orthogonal geometries work together to improve lateral stability and create organic interior experiences that respond to natural light, airflow, and domestic rhythms.

Clustered Spatial Layout Inspired by Nature

The architecture adopts a clustered plan, creating pockets of nature and open-air courtyards that extend living areas outdoors. These voids blur boundaries between shelter and landscape, encouraging a slower, nature-centric lifestyle.

Key spatial features include:

• Continuous interior-exterior earthen walls
• Flexible spatial flows defined by openings and voids
• Organic forms balanced with strict geometries for structural clarity

The result is a home that embodies biophilic design principles while embracing Japan’s tradition of living in harmony with the environment.

Environmental Performance Embedded in Material Systems

At 450mm thick, each wall includes inner and outer layers with an optimized infill cavity, reducing material use while providing superior insulation and acoustic comfort. Natural insulation fills the cavities, and embedded sensors monitor environmental behavior, temperature shifts, and moisture balance.

Construction sequencing challenges—printing walls before timber assembly—led to new detailing strategies that accommodate dimensional tolerances of additive manufacturing, evolving earthen construction techniques for real-world application.

Windows and doors use custom steel hardware to secure natural wood frames to earthen walls without compromising airtightness. Interiors are finished with site-sourced earth plaster, plant-dyed wood flooring, and low-impact materials that celebrate craftsmanship and environmental ethics.

Advancing a New Standard for Earth-Future Architecture

The Lib Earth House model B demonstrates how earth-based 3D printing can integrate with traditional building systems to address housing needs in a way that’s environmentally restorative, technically feasible, and deeply human.

By combining:

• Renewable and biodegradable materials
• Digital fabrication and traditional timber carpentry
• Passive performance strategies and biophilic planning
• Real-time sensing and long-term lifecycle performance

The project sets a precedent for future-proof housing rooted in place, ecology, and craftsmanship.

All photographs are works of  Akira Ito