This thesis aim is the development of an affordable, and energy-efficient tiny house design for Eco Caminhos, an ecological farm located in Nova Friburgo, Brazil. The study investigates how natural and recycled materials, particularly cob, bamboo, reclaimed wood, and stone, can be integrated with passive design strategies and off-grid water and electricity systems to create sustainable housing adapted to the humid subtropical climate of the Atlantic Forest region. 

The thesis was carried out through an eight-week field study at Eco Caminhos and applied a mixed-methods and design-based research approach. The methodology was combined literature review, site and climate analysis, material testing, field observations, semi-structured interviews, workshops and architectural design development. Environmental factors as rainfall, humidity, solar orientation, wind patterns, topography were analysed to understand the most appropriate climate-responsive design strategies. Material testing of cob mixtures and bamboo reinforcement was made to evaluate the materials for humid conditions.

The results demonstrate that earthen construction can be adapted to high-humidity environment with appropriate moisture protection and passive environmental strategies. Elevated stone foundations, large roof overhangs, breathable lime plasters, natural ventilation were identified as critical measures for improving durability. It shows that locally sourced materials can contribute to affordability, low embodied carbon. The off-grid systems as photovoltaic energy generation, rainwater management and greywater filtration support self-sufficiency and low-impact living. The study concludes that sustainable tiny houses using natural materials can provide a sustainable solution within humid subtropical climates when they are adapted to local conditions.