From inside the house, place one pipe wrench on the faucet's connection point to the pipe. Place a second pipe wrench (or adjustable wrench) on the connecting pipe fitting to hold it steady. This is crucial to prevent twisting or breaking the pipe. Turn the wrench on the faucet counter-clockwise to unscrew it from the pipe. It may require significant force if it's old and corroded. If needed, apply penetrating oil to the threads and let it sit for 10-15 minutes. Once loose, continue unscrewing by hand. After it's disconnected from the inside, pull the old faucet out from the exterior of the house.