Bath Room, Wall Mount Sink, and Concrete Floor An airtight building envelop helps naturally insulate the structure. The appliances in the house are energy-efficient, and use greywater recycling.  Photo 5 of 6 in The World's First Carbon-Positive Prefab House by Allie Weiss

The World's First Carbon-Positive Prefab House

5 of 6

An airtight building envelop helps naturally insulate the structure. The appliances in the house are energy-efficient, and use greywater recycling.