In short, plumbing pipes can be almost anywhere. They run through the ceiling beams in the basement and the floor beams in the attic. They are located between the uprights and cross the uprights of the inner and outer walls. A ball valve is a straight handle that runs parallel to the pipe when open.
To turn off a ball valve, the handle will move from a parallel position to a perpendicular position. The valve body has stops that only allow the handle to move from one direction to another and will stop the handle when it is completely perpendicular. clean water enters your home through a pipe called a “main water supply line” or “service line.” The rest of a house's pipes form the drain, drain and ventilation (DWV) system, which removes wastewater and prevents toxic sewer gases from entering the house. The pipe must be large enough to prevent moist air from condensing at the outlet point, freezing and thus blocking the pipe.
Your home's plumbing system has a water pressure regulator that ensures that the water entering your home isn't under so much pressure as to damage the pipes. A pipe under the sink will start about 1 ½ inches in diameter, but will connect to a pipe about 4 inches in diameter when you leave your house. The wastewater that leaves the house through the drain pipes uses gravity to flow from the upper floors to the main ventilated pipe and then exit through the connection to the sewer or septic tank. The cold lines reach all the accessories in the house and the water heater, where the hot water pipes conduct the water to the appropriate fittings.
Water travels from the city's main water line to your home's main water pipe, a large pipe (¾ inch or more) that leads to your house. Knowing a little bit about residential plumbing systems and the location of the pipes will benefit you in almost any situation that requires you to open walls. If you look at the exposed service pipes, you'll see that there are pairs of pipes that run parallel to each other throughout the house. If your water pipes are made of metal, you can use a simple metal detector to detect the path of your pipes.
Different states, counties, and cities have different codes regarding the materials and sizes of plumbing pipes. The size of this pipe will depend on your exact system, but it will be the largest pipe in your supply network. If you have a plumbing and water heating system, such as radiators, you'll find the pipes located next to the radiator and running behind the wall, or hidden in a socket. Before starting any home improvement project, whether plumbing or otherwise, you should familiarize yourself with the location of your pipes.