Climate activist and engineer Sonam Wangchuk’s home in Ladakh has drawn fresh attention after a home tour offered a rare glimpse into the eco-friendly residence. The house was featured in a video by YouTuber Amita Chhorgia Negi, known online as Tribal Girl, who was given access to the property for a walkthrough. The tour showcased a home built almost entirely around Ladakh’s climate rather than against it, using mud construction, passive solar design and water-saving sanitation systems.
Wangchuk, long rumoured to be the inspiration for Aamir Khan’s character in the 2009 film 3 Idiots (a claim Khan publicly denied more recently), has long worked on low-cost, climate-responsive architecture in the Himalayan region. His personal residence appears to be a continuation of the same design philosophy that shaped projects like the SECMOL campus and the Himalayan Institute of Alternatives, both of which rely on solar energy and earthen construction.
Mud walls and rammed-earth construction
As per the house tour video, the house is built using mud and rammed-earth techniques combined with wooden elements, a method long practised in Ladakh and neighbouring Himalayan regions. The thick earthen walls are said to help regulate indoor temperatures naturally, keeping interiors insulated against the region’s extreme winters and intense daytime sun.
Ladakh sits at an altitude of over 3,500 metres and experiences a cold desert climate, with freezing winters, low humidity and sharp temperature swings between day and night, conditions that make conventional concrete construction inefficient for heating and cooling. Rammed-earth walls, by contrast, are known for their thermal mass, meaning they absorb heat slowly during the day and release it gradually once temperatures drop after sunset.
How the passive solar heating system works
The tour noted that large glazed openings on the house are positioned to capture winter sunlight, while a dark-coloured thermal wall inside absorbs and stores that heat, releasing it back into the living space after dark. Wangchuk has reportedly said the system can maintain indoor temperatures of around 18-20 degrees Celsius even on nights when outside temperatures plunge well below freezing, without the use of a conventional heater.
This approach mirrors the passive solar design principles Wangchuk has applied elsewhere in the region. According to The Hindu, he has helped design and oversee the construction of several passive solar mud buildings across Ladakh, Sikkim and Nepal to demonstrate that energy-saving construction can work at scale. His solar-powered school built from rammed earth is reported to keep students warm even when outdoor temperatures fall to around minus 30 degrees Celsius.
A zero-waste sanitation system
Apart from the innovate heating system, the home also addresses water conservation — a pressing concern in a cold desert region with limited water resources. As per the video, the house uses urine-separating composting toilets instead of conventional flush systems.
Sawdust or dry earth is used to control odour, and the collected waste is left to decompose into compost that can later be used for agricultural purposes, reducing both water use and reliance on centralised sewage infrastructure.
Modern interiors and a communal dining tradition
Despite its rustic construction materials, the interiors of the house are reported to be far from austere. The tour reportedly showed sofas, vintage wooden furniture, a modular kitchen and attached bathrooms, wedding modern comfort to traditional building methods.
A communal dining layout has also been preserved, reflecting the Ladakhi tradition of cooking and eating together as a household. The property additionally includes a greenhouse and an apple orchard, extending the sustainable footprint of the home beyond its walls into food production suited to the region’s short growing season.
As interest in sustainable and climate-resilient housing grows across India, Wangchuk’s Ladakh home is likely to remain a widely cited reference point for architects and homeowners looking at passive solar and earthen construction as viable alternatives to conventional building methods.