Products The Sonoma Casita combines the ideals of net zero energy, net zero carbon, accessibility and advanced framing methods into an affordable by design home for aging in place. The attic is reached by a pull down ladder. This home is designed to be easily built by two workers and is adaptable for wildland urban interfaces. Main Floor: 600 square feet 1 Bedroom 1 Bath with 180 square foot storage attic Sonoma Cottage: 1101 square foot 1-3 Bedroom 2 Bath Main Floor Habitable Attic 3rd Bedroom Option Basement Option