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Concave Roof and Rainwater Collection in a Self-Sustaining Micro Home

Authors:
John Benedict Castillo, Alexandra Lagundi, Carla Leana Salao, Aron Cyrus Almirez
Concave Roof and Rainwater Collection in a Self-Sustaining Micro Home
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A concave roof design combined with an efficient rainwater collection system defines a self-sustaining micro home that maximizes space while promoting sustainable living practices.
5 key facts about this project
01
Utilizes a rainwater collection system integrated with copper piping for water efficiency.
02
Features a concave roof design that enhances light distribution and sound management.
03
Incorporates built-in storage solutions to maximize functionality within a small footprint.
04
Employs high ceilings and strategic openings to promote natural ventilation.
05
Adapts a tatami setup allowing for flexible living spaces and modular furniture arrangements.

LE' SPARROW is an exploration into micro housing, set in an urban environment where optimizing space is essential. Functioning as a self-sustaining living area, it caters to the demands of modern life that require flexibility within a limited footprint. The project emphasizes sustainable practices and thoughtful design to create a space that balances functionality with comfort.

Utilizing Built-in Storage

The layout features built-in storage that maximizes space while maintaining a clean aesthetic. This design choice allows residents to navigate their home easily, adapting their environment for various daily tasks. Every inch counts in micro living, and this approach ensures that each area serves a purpose, promoting an organized and efficient use of space.



Rainwater Collection System

One notable aspect is the rainwater collection system, which highlights a commitment to sustainability. This system captures rainwater from the roof and channels it through copper pipes to important areas like the water closet. By relying on harvested rainwater, LE' SPARROW reduces dependency on external water sources and supports a more self-sufficient lifestyle.



Ventilation and Climate Control

The design draws from principles of tropical architecture to enhance natural ventilation and manage indoor climate. High ceilings and well-placed openings allow air to flow freely throughout the space, creating a comfortable atmosphere. The venturi effect is utilized to improve air circulation, ensuring that the indoor environment remains pleasant without heavy reliance on mechanical systems.



Material Selection

Materials chosen for the project include cherry wood, natural oak, aluminum, and ceramic tiles, such as white and mosaic types. Lime wash concrete is also used, contributing to the overall durability of the structure. Together, these materials create a cohesive look that aligns with the functional goals of the design.



The roof features a concave shape that serves multiple purposes. It helps manage sound and distributes light, resulting in a warm and inviting interior space. The focus on these design elements showcases the project’s attention to detail and its aim to enhance the overall living experience.

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The Next House: USA — A Global Call to Reimagine the American Suburb

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Buildner is launching The Next House: USA, a global architecture competition that challenges architects, designers, and thinkers to reimagine the American suburban home for the 21st century. For decades, the suburban house has symbolized comfort and stability, but today it often reflects excess, isolation, and environmental strain. This competition asks: how can the American home evolve to address climate urgency, economic pressures, and shifting social values?

Participants are tasked with designing a prototype home of no more than 1,500 sq ft (≈140 m²) for a household of two adults and one child. The design should be compact yet generous, adaptable, sustainable, affordable, and replicable across diverse U.S. contexts. More than a design exercise, the competition aims to spark a conversation about how homes can support healthier, smarter, and more connected communities.

The total prize fund is $20,000 USD. The final registration deadline is May 20, 2026, and winners will be announced on September 22, 2026. The Next House: USA invites architects, students, and visionaries worldwide to redefine what the American home means today—and what it should mean tomorrow.

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