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Suspended Retreat of Steel and Oriented Strand Board Above the Forest Floor

Authors:
Münire Sude Argun, Nezihe Gökçe Kökcan
Suspended Retreat of Steel and Oriented Strand Board Above the Forest Floor
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Elevated above the forest floor, this cabin utilizes a cut tree for support and features a unique combination of steel and oriented strand board to create a meditative retreat focused on connection with nature.
5 key facts about this project
01
The cabin is supported by a cut tree, creating a direct connection to the landscape.
02
Three distinct levels maximize functionality within a compact footprint.
03
Triangular windows enhance natural light and provide panoramic views.
04
Steel framework ensures structural stability while allowing for a lightweight design.
05
A composting toilet optimizes space and promotes sustainability in waste management.

The Hanging Octahedron creates a unique living space that emphasizes a connection with nature while serving as a quiet place for meditation. The design elevates the traditional cabin concept above the ground, encouraging the feeling of being suspended in the air. This not only transforms the user experience but also integrates the structure harmoniously with the natural landscape.

Structural Integrity and Layout

The elongated octahedral form resembles a pine tree, enabling the cabin to rest on a cut tree with cables that extend to neighboring trees for support. Inside, the design is organized into three distinct levels that maximize functionality. The bottom level serves as the entrance and includes a basic toilet. The middle level provides warmth and comfort for living, while the lowest level can be used for storage or a water tank. The layout thoughtfully balances accessibility with practical needs.

Material Composition

Materials are chosen carefully to support the design's goals. The core structure uses steel to ensure strength and stability. The walls consist of triangular panels constructed from oriented strand board, with rockwool insulation for thermal efficiency. Double-glazed windows set in triangular frames allow for ventilation and bring views of the surrounding area, especially towards the nearby lake. This combination of materials enhances the performance of the cabin while maintaining a light and airy feel.

Energy and Sustainability

Energy efficiency is a key component of the design. A wood stove serves as the central heat source and also allows for cooking. Fresh air enters through a small duct that pre-heats the air using heat from the stove. Warm air rises into the sleeping area, creating a comfortable environment. A composting toilet in the lower level uses space effectively for waste management, reflecting a commitment to sustainable practices.

The Hanging Octahedron with its geometric simplicity and functional design encourages a strong connection to its environment, promoting a serene atmosphere while providing practical living solutions.

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The Buildner’s Unbuilt Award 2025: Celebrating Architectural Creativity and Visionary Unbuilt Designs with a Total Prize Fund of €100,000

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Competition organisers

The Buildner’s Unbuilt Award 2025 is an international architecture competition dedicated to recognizing and celebrating the value of unrealized architectural designs. It invites architects, designers, and students worldwide to submit visionary projects that have not yet been constructed, highlighting the power of ideas and the creativity behind the design process. By focusing on unbuilt work, the competition aims to bring forward concepts that shape the future of architecture and push the boundaries of the profession. 

Participants can compete in three categories based on project scale: Small Wonders (up to 100 m²), Medium Marvels (101–999 m²), and Large Visions (over 1,000 m²). Each category winner will receive €20,000, and additional prizes include honorable mentions, student awards, and a special Best Presentation Award. Winning projects will gain significant international exposure through Buildner’s publicity campaign and a feature article on ArchDaily, providing a unique opportunity to showcase creative ideas to a global audience. 

The Buildner’s Unbuilt Award 2025 encourages entrants to submit any type of unbuilt project, from conceptual visions to detailed designs, celebrating bold innovation without the constraints of realization. Important deadlines: registration closes on October 30, 2025; submissions are due by November 20, 2025; winners will be announced on December 17, 2025.

Buildner's Unbuilt Award 2025

Celebrating your unbuilt architecture visions with a €100,000 prize

100,000€ Prize / 2025 ideas COMPETITION
Prize 100,000 €
Eligibility Open to all
Final registration deadline 30 October 2025

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