Watch as an expert plumber explains how to turn off a water main in this free online video about replacing shower valves.
We are working on this leaky shower project. The reason I am outside is because we've got to shut the water off. You don't want to take that valve off without turning off the water. So the first thing you've got to do is locate where your water main is. There is one at the street, that is the main main, the city and then there is one that comes up to your house and it is usually on a wall outside of your garage or similar area. You can always recognize it because it is right below the water meter. It is right over here, I'll show you. Here we go. Here's our shut off valve and you want to absolutely do this before you touch anything as far as opening valves in your house because you are going to have a real mess if you don't do that. This is a ball and joint shut off. It is a newer one so it is real easy to use. This is the older style and you've got to twist and twist until that shuts down. This is one quick shot and your water is off. Now we are done with our job, I am going to show you how to come back out here and turn it on without having anything else go wrong inside the house.