Kotatsu are low tables with a heat source underneath, and a blanket draped over the top. For hundreds of years, Japanese have gathered around them in the cold winter months. They're cozy and comfortable; perfect for watching TV, studying and chatting to family and friends. Our guest, architect and university professor Watanabe Shinichi, talks about the social and environmental benefits of Kotatsu. And in Plus One, Kanoa tries out Kotatsu in some unusual locations.

Traditional Japanese homes, featuring earthen walls, wooden beams and thatched roofs, have been used for centuries. Built using local materials, they incorporated clever techniques to keep the interior warm in winter and cool in summer. Our guest, architect Maruya Hiroo, introduces several traditional houses, and explains what life was like for the people who called them home. And in Plus One, Matt Alt sees how the restoration and continued use of old houses is helping to revitalize a small town.