Smart buildings technology is becoming ever more important due to increasing demand in the market. One of the main issues of concern is the integration of different products made by different manufacturers designed for different functions in an environment with frequent changes. Therefore, in this paper a model is presented to deal with this issue and help manage the decision making processes in a smart building environment as well as support the relationships between manufacturers and customers. Also, this model should help manage conflicts between different customers’ requirements. The model is designed to accommodate future expansion in functions, properties, and services.