According to the graphics characteristics of metallic doors & windows design and based on the research of graphics dimension restriction problems. This paper provides a new method for parameterized design of metallic doors & windows in virtue of expression solution. In this method, the restrictions of graphic elements have been changed into the parameter expressions of sizes and positions of graphic elements. Through the calculation of such expressions, the parameter driven method has been reached. Thus the parameterization of graphics can be easier and quicker than before. It can be used to setup the open parameterized graphics libraries.