The purpose of this research is to gather qualitative data on the role of semi-open spaces, in traditional and modern Iranian houses in mediating climate and social relations, with the goal of regenerating these spaces in the design of contemporary Iranian houses. The research considers semi-open spaces in Iranian houses in three parts: historical reviews, data collection, and design recommendations. The first part of this study reviews three historical periods of Iranian housing development, and documents the variety and shapes that semi-open spaces take, their philosophical foundations, and the cultural, social, technological and economical importance they have had in people''s daily lives. The second part of the study includes a survey and structured interviews with individual Iranians in Tehran and Los Angeles to learn their attitudes, values, and domestic practices related to semi-open spaces. The third part of this research and analysis concludes with the goal of regenerating both the climatic and social functions of the semi-open spaces in the design of today''s Iranian houses.