embodiments of the present invention include methods for semi - automatic quantity takeoff from computer aided design drawings . for each drawing object a corresponding takeoff object is created . a takeoff object may include the dimension of geometry 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 .