Sharing quantity takeoff data between computer aided design projects

摘要

Embodiments of the present invention include methods for semi-automatic quantity takeoff from computer aided design (CAD) drawings. For each drawing object a corresponding takeoff object is created. A takeoff object may include the dimension of geometry (e.g., numerical, lineal, area) to quantify, the object parameter to be quantified for all instances of the object, and the takeoff calculations to be performed. After a takeoff object is defined, the corresponding instances are automatically identified and quantified. The cost of each instance is then calculated and added to the project cost. Using automated methods, instead of manual techniques, reduces errors and increases the accuracy of the generated cost estimate. Advantageously, the takeoff objects may be saved in the system database and reused for different projects, thereby ensuring consistency between projects. Furthermore, reusing takeoff information, both between instances of an object and between projects, reduces the time required to perform cost estimates.