How to Change Out Water Supply Pipes

Shut the water off at your water main, which is normally near the home's water heater.

Cut out the old pipes using a grinder and a metal cutting disc. Use a diamond bit blade to cut out iron pipes. Remove the pipes once they are cut.

Clean the ends of the old pipes you cut with the cutting disc with an emery cloth to remove the harsh ends and burrs. Measure and cut new copper pipe to fit into your installation with a hack saw. Supply pipes normally rise up 18 to 24 inches from the floor, but your faucet or plumbing may require a different set up. Dry fit the couplings and new pipe by sliding the couplings and pipes together where you want them installed. Cut the pipe to fit appropriately.

Remove the pipes and couplings. Coat the ends in solder flux and re-install the pipes. Heat the seams of the couplings and pipes with a blow torch. Touch the solder to the seams and let it melt and fill in the seams. Repeat this process until all seams are filled with solder. Let the pipes cool.

Coat the pipe ends in solder flux. Place the water shut off valves onto the ends of the pipes. Heat and solder the valves in place with the blowtorch and solder.