The Threshold of Urban Sustainability within the Traditional Cities: Traditional Alnajaf city as a case study

Successful urban interventions in traditional cities must be thoughtful, accurate and wise intervention, so the research assumed that urban sustainability represents a contemporary development intervention that tries to regulate the performance of urban products (components - dimensions) in traditional cities within three factors which are, the right time, right place, and positive performance. The traditional Alnajaf city in Iraq was taken as a case study, morphologically; the general shape of the city was classified into five main parts and examined them with physical dimension that was depended on the concepts of sustainability threshold according to the descriptive data. From this analysis the research determined the right, time and place to achieve the best sustainable intervention. The research found that there is a variation in the level of sustainability in traditional Alnajaf city resulting from the different type of intervention at the level of the constituent parts of the urban fabric. Thus, it is possible to take advantage of the limits of urban sustainability (The Threshold) in creating a balance between the type of urban intervention and the needs of the original city to preserve the traditional cities, including traditional Alnajaf city.