Mass source tutorial in sap2000

Remember while specifying mass source, when you choose the third option i.e from element, loads etc.... DO NOT SELECT THE DEAD LOAD CASE OR THE DEAD MASS OR SELF WEIGHT OF YOUR STRUCTURE WILL GET DOUBLED. i.e only select the loads that you've assigned to the model if you want them to act as additional mass to the structure. eg. dead load of furnitures in building.