Job · Gas water heaters
Gas water heaters: permits and who does the work
If you smell gas, leave the building first; a gas water heater is a licensed professional's job, and Arlington, Fairfax County and DC each treat the permit differently.
Revised November 3, 2026 · who makes this map
| Place | What happens there | Turn to |
|---|---|---|
| DC | The Department of Buildings plumbing permit application asks for the master plumber or gas fitter's name, signature and license number. DLCP's Board of Industrial Trades licenses plumbers and gas fitters. | Sheet 1 |
| Arlington | A plumbing and gas permit is needed to add, remove or relocate appliances. Replacing the same type, size and location is exempt, but only if the appliance is not gas-fueled, so the exemption does not apply to gas. | Sheet 6 |
| Alexandria | The city's permit page says trade permits come after the building permit under the Virginia codes. We could not confirm a separate rule for gas heaters. | Sheet 8 |
| Fairfax County | A Household Appliance permit covers replacement of appliances including water heaters, with one final inspection. The county's page says gas appliances are included when no new gas piping is installed and are not exempt from permits. | Sheet 12 |
| Vienna and the others | Gas appliance permit rules for Falls Church, Herndon and the City of Fairfax are unconfirmed. Vienna's page says Fairfax County acts as its building official. | Sheet 14 |
What this page covers
This page tells you who has to be involved when a gas water heater is installed or replaced. It gives no installation or repair steps and none are meant to be implied. Gas piping, venting, valves and burners are work for a licensed professional, and in most places they need a permit.
Leave first
Washington Gas says that on smelling natural gas you should leave your building or location immediately, and only then call 911 and its emergency leak line. It adds that doors and windows may be left open only as you leave, if possible. Nothing about a heater is worth staying for.
The permit, place by place
In DC, the permit application names the master plumber or gas fitter responsible. That license is checked against DLCP records through the Department of Buildings' permit wizard. Find the lookup under check a license.
In Arlington, the county's page says replacing like with like is exempt only when the appliance is not gas-fueled. For a gas water heater, you should assume a permit is needed and ask the county. A homeowner may pull permits for their own single-family house or townhouse, and the county does rough and final inspections.
In Fairfax County, the Household Appliance permit exists for direct replacement of appliances in a residence, including fuel-fired ones. The county says property owners may pull permits in their own name but strongly recommends a properly licensed contractor pull them, so the county can help get defective work corrected. Apartments and condominiums are treated as commercial.
For other places, see permits by place. The list of what each government confirmed is short; where we could not confirm, ask the building office.
What to ask a licensed plumber
- Who pulls the permit, and what is the permit number?
- Does the quote include venting, gas connection and the final inspection?
- Will they take away the old unit?
- What is the license number, and does it match the lookup for your place?
Heaters also sit close to other topics: an old house may have asbestos pipe wrap near the unit, and the main shutoff matters for any plumbing job. Do not attempt any of these yourself.
To compare tank types and sizes before you talk to a licensed pro: water heaters at PlumbingSupplyAndMore (that store has the same owners as this map).
If the pilot or burner seems wrong
Do not investigate. If there is any smell of gas, apply the leave-first rule above. If there is none, call a licensed professional and describe what you saw. We do not give relighting or adjustment instructions.
Check your own address
- Look up your plumber or gas fitter: DLCP for DC, DPOR for Virginia.
- Ask the county or city building office whether a gas water heater replacement needs a permit at your address.
- In Arlington, do not treat the exemption as applying to a gas heater.
- In Fairfax County, ask whether the Household Appliance permit or the Residential Plumbing permit applies, which depends on whether new gas piping is involved.
- Keep Washington Gas's emergency number, 844-927-4427, somewhere you can reach from outside the house.
Survey notes: sources for this page
- Washington Gas, natural gas safety. Opened November 3, 2026.
- Fairfax County, household appliance permit. Opened November 3, 2026.
- Arlington County, plumbing and gas permits. Known to us only from a search listing of the page; the site would not open for us.
- DC Department of Buildings, permitting FAQs. Opened November 3, 2026.
- DLCP Board of Industrial Trades. Known to us only from a search listing of the page.
- Alexandria new residential plan submittal requirements. Known to us only from a search listing of the page.; not opened.
- Town of Vienna, residential projects. Known to us only from a search listing of the page.; not opened.