Rex is unincorporated, so a tankless water heater install is permitted through Clayton County rather than a city. Clayton County Water Authority supplies the water, and most homes date from the 1990s on. Call the number on this page to be connected with a local plumber in Rex.

Who issues permits for a Rex home?
Clayton County. Rex was incorporated as a town in 1912 but its charter was repealed in 1922, so today Clayton County Community Development handles building, mechanical, electrical and plumbing permits for remodels, repairs and new construction. The office is at 121 South McDonough Street in Jonesboro, (770) 477-3569. A tankless conversion adds gas piping, a new vent and water connections, so expect it to be permitted.
Will my Rex house need much work?
Usually not a lot. The median home in Rex was built in 1995, and about 20% predate 1980. Most heaters sit in a garage or utility room, and a wall-mounted tankless unit can often go in the same area with a short vent to an outside wall. The plumber will still check whether the gas pipe from the meter can carry a tankless burner at full fire, since builders sized it for a tank. A condensing unit needs a drain for condensate, and every unit needs an outlet for its controls. Older homes near Rex Village may need a longer vent route. Bigger two-story homes from the 1990s and 2000s sometimes need a higher-capacity unit or recirculation so the upstairs bath does not wait on hot water.
What should I know about the water?
Clayton County Water Authority provides water and sewer across the county. Its supply comes from the Little Cotton Indian Creek, Shoal Creek and Pates Creek watersheds, with the Flint River as a supplement. The fact sheet does not include a hardness figure, so a water test is the way to set a flush schedule. CCWA also tests residential backflow devices itself and offers a service line inventory lookup.
Local note
Because Rex has no city hall, residents sometimes assume a heater swap needs no permit. The county permit office is the one to check with, and the plumber normally handles the paperwork. Atlanta Gas Light owns the gas pipes in Clayton County; the marketer on your bill does not handle leaks. If you smell gas, leave first, then call 911 and AGL at 877.427.4321 from outside.
Tankless Water Heaters questions in Rex
Do I need a permit to switch to a tankless water heater?
What should I do if I smell gas near my water heater?
Can a tankless setup get hot water to a far bathroom faster?
Can an electric tankless heater handle a whole house?
More plumbing services in Rex
Tankless Water Heaters nearby
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