Traditional bridge coating area calculation uses approximate algorithms, which have problems such as imprecise calculation results, non-intuitive calculation results, and unable to verify the accuracy of the calculation results. This paper introduces a method of high-precision coating area calculation using BIM technology through the form of a practical case. The study first argues that the order of the faces forming the solid components of the Revit parametric model remains unchanged after the geometric dimensions change. Then, by introducing Rhino modeling software to convert the Revit model format, and using Grasshopper visual programming technology, the program can identify the surfaces of a component that need to be coated after recognizing the parameterized model established by Revit. After that, the program can identify the same parameterized component in batches according to the face number, achieving the goal of rapid and accurate calculation of bridge coating area. This study innovatively uses visualization means to solve the problem of bridge coating area calculation using BIM models.