Do You Need a Permit to Replace a Water Heater in Marietta & Cobb County? (2026)

Plumbing Tips June 22, 2026 · Metro Atlanta, GA

Short answer: yes. If you are swapping out a water heater anywhere in Marietta or Cobb County, the work needs a plumbing permit and an inspection. A lot of homeowners are surprised by that. A water heater feels like a quick appliance swap, like changing a dishwasher, so people assume it is no big deal. But a water heater ties into your water supply, your gas line (or a 240-volt circuit on electric units), pressure controls, and venting. Georgia treats it as real plumbing work, and both the City of Marietta and Cobb County require it to be permitted. This post walks through who needs a permit, what a licensed plumber actually handles, and what can go wrong when the work is done off the books.

Yes, a permit is required in both Marietta and Cobb County

The rules depend on whether your address is inside the City of Marietta or in unincorporated Cobb County, but the answer lands in the same place either way.

The City of Marietta requires a plumbing permit for work done on a plumbing system, and that list specifically includes water heaters along with water supply, sewer, and gas lines. Permits in the city are handled through the SagesGov online portal, and a water heater replacement also needs an inspection that the contractor schedules. The homeowner has to be available to let the inspector in.

In unincorporated Cobb County, the county code says any contractor or owner doing plumbing construction has to pull a permit through the Community Development Agency before the work starts. Residential permits there are good for 180 days, so the job needs to be completed and inspected inside that window.

Because these requirements do change and fees get updated, it is always worth a quick call to confirm the current process for your exact address before the work begins. If you hire a licensed plumber, this is handled for you. We pull the permit, do the work to code, and meet the inspector. That is part of the job, not an add-on.

What the Georgia plumbing code actually requires

Georgia adopts the International Plumbing Code with state amendments, known as the Georgia State Minimum Standard Plumbing Code. That code, plus local enforcement, is what the inspector is checking against. A few of the items that come up most often on a water heater install:

Thermal expansion tank. If your home is on a closed water system (common when there is a backflow preventer, check valve, or pressure-reducing valve on the line), a thermal expansion control device is required. The code calls for it to sit downstream of those valves on the cold water supply.
Temperature and pressure relief valve. Storage tank heaters need an approved, self-closing T&P relief valve. That valve is a safety device and is not allowed to double as the thermal expansion control, which is why the expansion tank is separate.
Shut-off valve. The cold water supply needs an accessible shut-off so you can kill the water fast during an emergency or for service.
Drip pan and drain. A tank-style heater generally needs a pan piped to an approved location, so a slow leak drains away instead of sitting under the tank and rotting your floor.
Proper venting and gas connection. On gas units, the venting and gas hookup are checked carefully. This is the part where bad work turns dangerous.

Tankless units have their own set of details around gas sizing, venting, and condensate. If you are weighing a switch, our water heater repair and replacement page covers tank versus tankless and what fits Metro Atlanta homes.

Why permits and inspections matter

The permit is not just paperwork. The inspection is a second set of trained eyes on a system that handles hot water under pressure, often with a gas flame or a high-voltage circuit. Get the venting wrong on a gas unit and you can vent carbon monoxide back into the house. Skip the expansion tank on a closed system and pressure has nowhere to go, which stresses the tank, the relief valve, and your pipes. The inspector is there to catch the things that are easy to miss and expensive to ignore.

It also creates a record. When the job is permitted and passes inspection, there is documentation that the work was done right. That protects you down the road.

The risk of unpermitted work

Cutting the permit to save a little money usually costs more later. Here is what tends to happen:

Insurance headaches. If an unpermitted water heater leaks and floods, or a gas issue causes a fire, your insurer can push back on the claim because the work was not permitted or done by a licensed plumber.
Problems at resale. Buyers and their inspectors look for permit history. Unpermitted work can stall a sale or force you to redo the job correctly under pressure during closing.
Safety risk. No inspection means nobody confirmed the venting, gas connection, or pressure controls. Those are the exact failures that hurt people.
Fines and tear-outs. If the county or city finds unpermitted work, you can be required to permit it after the fact, open up finished work for inspection, or redo it.

How A&G Plumbing & Drain handles it

A&G Plumbing & Drain has been a family-owned, licensed and insured plumber in Marietta, GA since 2006, with a 4.9-star rating across 420+ reviews. When we replace a water heater, we pull the permit, install to the Georgia code, add the expansion tank and pan where required, and meet the inspector so it passes the first time. You get a heater that works, a job that is on the record, and no surprises later.

We offer fast scheduling and same-day service when available during business hours. Call us at (770) 627-4421 to set up your water heater replacement.

Frequently asked questions

Do I need a permit to replace a water heater myself in Marietta?

The work still requires a permit and inspection. Some Georgia jurisdictions allow a homeowner to permit work on their own primary residence, but the rules vary and the inspection still applies. Because of the gas, venting, and pressure controls involved, most people are better off using a licensed plumber. Confirm the current homeowner rules with the City of Marietta before you start.

How much does a water heater permit cost in Cobb County?

Permit fees change and depend on the scope of work, so we do not want to quote a number that could be out of date. The City of Marietta calculates fees through its SagesGov portal, and Cobb County sets its own schedule. When you hire us, the permit cost is folded into your quote so you see the full price up front.

How long does a permitted water heater replacement take?

The install itself is usually a few hours for a standard swap. The permit is typically issued quickly, and the inspection is scheduled separately, often within a day or two. Tankless conversions take longer because of venting and gas work. We handle the scheduling so you are not chasing it.

What happens if my old water heater was never permitted?

That is common and not a reason to panic. When we replace it, we permit the new install correctly, so you end up with a properly documented unit going forward. We do not need to undo the past, we just do the new work by the book.

Do I need an expansion tank when I replace my water heater?

If your home is on a closed water system, which is common in this area when there is a pressure-reducing valve or backflow preventer on the line, then yes, the Georgia code requires a thermal expansion control device. We check your setup and install one when it is needed so the job passes inspection.

Can A&G come out the same day for a water heater that died?

Often, yes. We offer fast scheduling and same-day service when available during business hours, which are Monday through Friday, 9am to 5pm. Call (770) 627-4421 and we will get you on the schedule and pull the permit so it is done right.