Roof is regarded as one of the main components of a building and understanding how to design it by the locals throughout the time plays a key role as their answer to the structural issues and problems arising during the implementation will be helpful for the new approaches to vernacular architecture. In this study, by investigating the roof of the houses in Banadkook-Dize village in Taft county (Yazd, Iran) from the appearance of the village, the reason of form changes and their method of construction have been examined. To do this, the history of the village was divided into four different era; the first era was when the village came into existence and the villagers used to live in the citadel; the second was when the citadel had no more capacity and the people went out of the citadel to construct buildings near it; the third was the constructions after the destructive flood of 1956 in the village; and the fourth one is the current construction status of the village. Except for the first period which the citadel is almost completely destroyed and no information is left, five houses were studied for each era throughout field study and an interview was conducted with the owners. The results reveal that two general forms can be seen in the form of roof in the village, that is flat and curved roof, each of which having a different method of construction. There are different reasons involved in their changes including residents' skill in its construction, finding new building materials, keeping prices reasonable prices and responding to functional demands.