Homeowner noticed an exhaust smell from his water heater. The water heater had single wall venting from the water heater to the garage ceiling. The garage is a non conditioned space and per code the exhaust vent needs to be double wall. Shut the water off at the street and drained system down cut out section of copper piping from the cold side for the water heater. Removed the single wall venting and replaced with the double wall and secured. Replaced hose Bibb shut off valve and cold inlet shut off valve and repiped to the water heater. Replaced the main shut off valve with a ball valve. Turned water on and purged air from the system. Insulated water lines and tested. Everything is working properly at this time.