Before deciding the type of plumber for your house, you must understand the plumbing system of around your house. The plumbing system allows the passage of hot water and the water is heated on the way to the tap. The portable cold and hot water supply plumbing system are installed in the back yard of the house close to the exterior of the bathroom. Fuel gas piping is the most common plumbing system after portable water system plumbing and drainage venting plumbing.