IJFPS, Vol . 1, No.1, January 2011 Name of First Author 1 IJFPS International Journal of Fundamental Physical Sciences Original Research Paper Open Access Journal,2011 ISSN :2231-8186 www.ijfps.com Recognizing the concept and performance of Iwan in Iranian architecture with a focus on influence on contemporary architecture of Hamedan Sara Soleymani, Yahya Kasha Nahanje, Elham Sadeghian 1 Departement of architecture, PHD, Science and Technology University, Iran. 2 Departement of architecture, post graduate student, kurdistan University6514763458, Iran, (yahya_kashi@yahoo.com /09188137155) 3  Departement of architecture, post graduate student, Islamic Azad University of Hamedan, , Iran. (Received 20 January 2011; Published 13 May 2011) Abstract While recognizing the performance of Iwan in Iran traditional architecture and its role as a semi-open space, we aim to investigate the mutual impact of this element in Iran contemporary architecture. Iwan is considered as a space in Iranian architecture with a performance and conceptual wealth and its presence along with as open space results in a valuable structural dimension. In this research, we try to find the roots of this space semantically and symbolic ally and the history and emergence of Iwan in Iran architecture. Then, the change of performance or form of Iwan is analysed in contemporary architecture of Hamedan. The results show that properly exploitation of this element in Iran architecture can lead to the promotion of spatial – structural quality. Key words: Iranian architecture, Iwan, semi open space, spatial structure, hamedan city. INTRODUCTION Although time makes the change of needs and concepts inevitable, some human needs, referring to mental and individual characteristics have sustainability theme and may only change in form. The everlasting need of human to open space has been expressed in various forms of court and Iwan. What is important about the traditional architecture is attention to semi open spaces and Iwan as a sustainable climatic element which promotes the spatial structure and quality of house. Iwan as a semi open space has unique nature and characteristic and is a response to some environmental needs of human. The understanding of the performance and function of Iwan can help to revive its features to adapts with new architecture. MATERIALS AND METHODS The history of Iwan in iran architecture As wolfant Glays thinks, Iwan in Iran architecture was built in two types: parsi and parthi method. The mostancient iwan belong to parsi metohod,as a covered and columned space with a flat section. (Fig 1) . This method was originated from orar to architecture. Figure 1. Pasargad palace Influencing the nued architecture. Little is known about or arto architecture but its main themes can be obtained from a curved motif in Musasir. The invention of Iwan originated from Apadana of achemenids and continued in palaces of Alhamr in Ashour of Ashkanian was related to Sassanid period in which the establishment of Iwan became common in place design. Firouzabad place and Kasra arch are examples of architectural embodiment of divine power or king powen. Glancing at the history of Iran architecture shows that from Achemendis onwards, the house with Iwan has been the integral feature of Iranian architecture along with columned and domed buildings. The Iwan around the central court and tripartite divisions (fig 2) were almost always used in Iran. Figure 2. Labaf s Mansion, Isfahan After the instruction of Islam in Iran, the construction of Iwan continued. In Safavid and Qajar period, a number of houses had Iwan in one or fronts while Iwan of Aalighapou and Chelsotun palaces remind the columned Iwans of Perspolis and Pasargad which shows of continuous trend in architecture. In order to investigate iwan and how it has changed in Hamedan architecture contrastive analysis method is utilized. Sample buildings belonging to two historical eras are analysed. So some criteria are considered for iwan which are analysed in old houses. Then these criteria are analysed in the same application in modern architecture. RESULTS AND DISCUSSION 1. concept and performance as an archetype Iwan has been defined as an arch or high seating covered with roof and the open front, while in some books the semi-open nees has been focused on as making an intermediate feature of empty and full space. This space is considered to be intermediate in terms of light and temperature. In the book the sense of unity, Iwan is said to be containing the features of limiting the space and making a transition from world to other world. In fact, Iwan, in a metaphysical interpretation, is an intermediate of room (body) and court or garden (mind). In fact, Iwan, as the most important space in Iran architecture, has been displayed in a variety of forms such as balcony or spring-sleeping room. Ravagh, another variety of Iwan, is a three-closed front space with a height the same as that of roof. One of the spatial features of traditional houses in Iran was the presence of three varieties of space; open spaces, open spaces and closed spaces, and three covering elements, upper, walled,