For heat setting we calculate the gsm by following formula Required GSM (Customer std)x1.07×1.02×1.06×1.04= gsm after heatsetting. Here we assume 1- 7% process loss of cotton 2- 2% process loss of lycra on account heatsetting 3- 6% length shrinkage in final product 4- 4% width shrinkage in final product condition to that after heatsetting the fabric has shrinkage of 3% in length and 3% in width