A thorough understanding of problems such as dry bands and electric discharges can only be achieved through accurate determination of electric field distribution along the insulator surface under a range of atmospheric conditions. Simulations of the electric field over the surface of the insulators are intended to determine the high stress regions on the surface of the insulator. A commercial finite element package is employed for insulator modelling to determine the electric potential and the electric field distribution along the creepage distance of the insulator.