There are some main keys to know while waiting for a plumber. First of all know where your main water shut-off valve is located. Second, know where your electrical box is located in case of an emergency. If your having a flood in a certain area on a specific fixture turn off the shut-off valve that goes with the fixture. If you don’t have a shut-off valve on that fixture have a plumber install one before it’s to late. If you can’t isolate a water leak locate the main water shut off valve and turn it off immediately. This doesn’t solve the problem but it will be the best thing to do before the professionals arrive. Have the plumbers help you locate all the shut-off valves and have some labels to make life easier in the future.

Ball Valve

Gate Valve