Step 2 · Shut Off Water Supply and Drain Pipes
Turn off the main water supply valve for the entire house. This is typically located in a basement, crawlspace, or utility closet near where the water service enters the home. After shutting it off, open the lowest faucet in the house (like a basement sink) and the faucet closest to your work area. This will relieve the pressure and drain most of the water from the system. Place a bucket and have some towels ready directly under the section of pipe you will be cutting.