The idea of a central courtyard has been used for massing design of the "2500- unit complex of national housing project", so that 2500 housing units have been defined in seven neighborhood. The courtyards of these neighborhoods act as semi-public spaces for the residents, which include all the services required at the neighborhood level. Also, considering green spaces and parks will be very effective in shaping the landscape, improving the quality of life, the desired mental image and climatic comfort. Considering public spaces for events and defining creative activities that are designed with the participation of residents, promotes environmental, social and economic sustainability. One of the most important issues in locating of buildings was the sun and shadow pattern and how the building receive sun rays. In order to achieve the minimum shading of the masses on the other one and also to create a dynamic sky line, the height change of the masses was highly considered and an attempt was made to observe this height change for all buildings. Another special feature of the project is green terraces with an average area of 6 square meters for each of the residential units.