Evaluation of Functional Efficiency of Space in Architecture of Two-Sided Houses Built in the First Pahlavi of Shiraz(Case Study: Razmjoo and Mostaghni Houses)

Since the first Pahlavi architecture is a new chapter in the creation of space and so far little research has been done on the houses of Shiraz that qualify and valuable criteria to protect and model their architecture; Based on this, this research aims to evaluate functional efficiency of space in architecture of two-sided houses of first Pahlavi construction in Shiraz, so that by improving the quality of housing architecture, it can achieve sustainable development of urban housing. Therefore, in terms of the objective, it is an applied research, and in terms of the data collection method, it is a non-experimental descriptive research of survey and case type. In this way, first, by using library sources and documents, the concept of functional efficiency of space in the residential architecture of the first Pahlavi of Shiraz was investigated and the factors affecting it were extracted; Then, by drawing explanatory diagrams, the spatial relationships in the selected houses were analyzed using the way of life and space syntax, and the spatial organization of the houses was examined from the point of view of movement, arena and functional systems. Following the ranking of factors affecting the performance efficiency of space in the first Pahlavi residential architecture of Shiraz, based on the process of analytical analysis, it was discussed. Then the performance efficiency of space was evaluated in the architecture of the selected houses. The obtained results show that the components of "accessibility" and "flexibility" in the movement system of space, the component of "penetrability" in the system of staging space, and the components of "interconnection" and "integration" in the functional system of space as indicators, positive indicators with an increasing effect, as well as the "average relative depth" component in the space staging system and the "relative order" and "separation" components in the functional space system as negative indicators with a decreasing effect on the level of functional efficiency are considered as space. The compatibility rate values are less than 0.100, hence the criteria are compatible in terms of mathematical logic and the calculations are correct. Therefore, the criteria of revitalizing the local identity and culture, form and direction of the optimal location of the mass-space, ecological orientation, compliance with the formal-spatial hierarchies, introversion, establishing security and safety, using light and natural ventilation, connecting with nature and natural elements, physical and visual accessibility, continuity of the level of human activities, fit between space, form and activity, existence of open (public), closed (private) and semi-open-closed (semi-public-private) spaces, respecting adaptability and flexibility, creating diversity and attractiveness, paying attention to beauty and avoiding futility are the factors affecting functional efficiency of space in residential architecture of first Pahlavi of Shiraz, which are ranked according to their importance, as well as the options (yard + two-sides-construction of two opposite fronts) and (yard + two-sides of the L-shaped structure) respectively have the highest appearance of the mentioned factors and, accordingly, the highest level of functional efficiency. It is considered that by strengthening the positive components and weakening the negative components on functional efficiency of space in residential architecture, the design process can be guided in an architectural format.