Publication date:
March 16, 2025
Rural Family Builds $40,000 Greenhouse ADU for Self-Sufficiency
A family in rural Washington constructed a $40,000 greenhouse accessory dwelling unit (ADU) to grow food year-round and increase self-sufficiency.
Renewables
In a move towards greater self-sufficiency, a family in rural Spokane, Washington, has invested $40,000 in constructing a greenhouse accessory dwelling unit (ADU) on their 140-acre property. The project, completed in 2024, aims to enable year-round food production, particularly during the harsh winter months.
The 200-square-foot structure utilizes rammed earth building techniques, an ancient method known for its low carbon footprint. This approach, which involves compacting a mixture of soil, clay, and gravel, offers superior temperature stability compared to traditional greenhouses, creating an ideal environment for growing fruits and vegetables.
The greenhouse ADU incorporates passive solar design principles to optimize heating and cooling. Its north-south walls are twice as long as the east-west walls, with a 10-inch gap between them. PVC pipes beneath the footing and holes at the top of the walls create a natural heat pump for air circulation. The roof, made of transparent polycarbonate sheets, allows sunlight entry while retaining heat.
To further regulate temperature, the structure includes a Glauber's salt bin system, designed to maintain internal temperatures between 40° and 85° Fahrenheit. This sophisticated climate control mechanism is still being completed in phases.
While the primary purpose of the ADU is food production, the family is currently using it as a yoga studio, demonstrating its versatility. The project not only serves practical needs but also connects the family to sustainable living practices and cultural heritage.
This innovative approach to local food production and self-sufficiency could serve as a model for others looking to reduce dependence on traditional supply chains and enhance food security. As energy costs and climate concerns continue to impact global agriculture, small-scale, climate-controlled growing environments like this may become increasingly valuable in ensuring stable food supplies.
The 200-square-foot structure utilizes rammed earth building techniques, an ancient method known for its low carbon footprint. This approach, which involves compacting a mixture of soil, clay, and gravel, offers superior temperature stability compared to traditional greenhouses, creating an ideal environment for growing fruits and vegetables.
The greenhouse ADU incorporates passive solar design principles to optimize heating and cooling. Its north-south walls are twice as long as the east-west walls, with a 10-inch gap between them. PVC pipes beneath the footing and holes at the top of the walls create a natural heat pump for air circulation. The roof, made of transparent polycarbonate sheets, allows sunlight entry while retaining heat.
To further regulate temperature, the structure includes a Glauber's salt bin system, designed to maintain internal temperatures between 40° and 85° Fahrenheit. This sophisticated climate control mechanism is still being completed in phases.
While the primary purpose of the ADU is food production, the family is currently using it as a yoga studio, demonstrating its versatility. The project not only serves practical needs but also connects the family to sustainable living practices and cultural heritage.
This innovative approach to local food production and self-sufficiency could serve as a model for others looking to reduce dependence on traditional supply chains and enhance food security. As energy costs and climate concerns continue to impact global agriculture, small-scale, climate-controlled growing environments like this may become increasingly valuable in ensuring stable food supplies.
