Nakesh (Dehumidification Channel): A Conservative Element Against Moisture in Historic Buildings in hot and arid areas in center of Iran Case study: Nakesh building process in Akhavan-e-Sigari historic House, Yazd, Iran

In center of Iran, moisture has been a serious problem regarding historic buildings, especially when most of them were built using adobe. Traditional architects have designed fantastic elements like Nakesh to control and eliminate moisture. Aiming to document as well as conserve and re-use of an original conservation technique, the present article asks these questions: What is Nakesh in the Historic Buildings in hot and arid areas in center of Iran? How does it work? How is it built? To answer these questions, different research methods were utilized, including literature review, field observation of original cases, and focusing on Nakesh building process in Torab historic House as a case study. Nakesh has different types; however, their mechanism is the same. The kind that will be specifically studied in this research is a vertical channel around the courtyard in central courtyard building. The channel works based on a natural ventilation which absorbs the moisture from its surrounding soil as a conservative element. Transferring and evaporating moisture by Nakesh led to save the foundation of building elements; the moisture permeates into the ground then into the building bases due to small pool, garden, and watering in the courtyard or the moisture which comes up through the ground. Construction materials, techniques to build floor, wall, and the ceiling of Nakesh, and the plan and section of it in each case are different, depending on building properties. These factors play a key role in Nakesh function.