Water heaters in Houston: repair, replace or go tankless

Repair or replace?

Symptom	Usually	Why
Water pooling from the tank body or seams	Replace	A leaking tank can’t be repaired
Leak at a fitting, valve or the drain valve	Repair	These parts can be replaced
No hot water (gas)	Often repair	Pilot, thermocouple or gas-valve issues are common
No hot water (electric)	Often repair	Heating elements and thermostats can be replaced
Rumbling or popping	Maintenance first	Usually sediment or scale on the bottom of the tank
Rusty hot water	Inspect	It may be the anode or tank corrosion. Ask the plumber to show you which
Tank at or past 10 to 15 years with recurring problems	Consider replacing	That’s the typical storage-tank lifespan, according to the DOE

Tank or tankless?

Department of Energy figures help frame the choice:

• Efficiency. Tankless units are 24% to 34% more efficient than storage tanks in homes that use 41 gallons or less of hot water a day. In homes that use about 86 gallons a day, the gain is 8% to 14%.
• Lifespan. The DOE says most tankless units last more than 20 years, compared with 10 to 15 years for storage tanks.
• Flow. Typical tankless output is 2 to 5 gallons per minute. Gas units generally deliver more than electric ones, so a large household running showers at the same time may need a bigger unit or more than one.

Switching to tankless in an existing Houston home often means changing the gas line size, venting or electrical service. Get that work included in the written quote, not added later.

Houston’s permit and installation rules

• Permit. “A plumbing permit is required for the replacement and installation of water heaters” in Houston. A master plumber registered with the city must obtain it, and an inspection follows.
• Doing it yourself. A homeowner who owns and lives in the house as a registered homestead can get a Homeowner’s Plumbing Permit and do the work personally. An inspection is still required.
• Garages. Under Houston’s code amendments, burners and ignition sources in a residential garage must be at least 18 inches above the floor, unless the appliance is certified as resistant to igniting flammable vapors.
• Attics. An attic water heater must be reachable by a permanent or fold-down stairway or ladder rated for 350 pounds.
• Suburbs. Sugar Land’s homeowner brochure says permits are required for water heaters. Missouri City allows water heater inspections by remote video inspection. Check with your own city.

A missing permit can cause problems at inspection or resale, so ask for the permit number on any replacement quote.

Hard water and scale

Houston’s main water system averaged 135.5 ppm total hardness in the city’s 2025 water quality report, with a range of 43.5 to 229 ppm. That’s about 7.9 grains per gallon by our conversion. Minerals settle in tanks as sediment and build up as scale inside tankless heat exchangers. That’s why many plumbers recommend flushing tanks regularly and descaling tankless units on a schedule. Ask what maintenance the manufacturer’s warranty requires.

After a flood

CenterPoint advises having any gas appliance that was in floodwater, water heaters included, checked by a licensed plumber or gas appliance technician before using it again.

Questions to ask for a replacement quote

• Is the permit included, and who pulls it?
• What brand, size and fuel type are you quoting, and why that size?
• Does the price include haul-away, a new drain pan, expansion tank, venting or gas line changes if needed?
• What is the warranty on the tank and on your labor, and what maintenance does it require?