Gas Line Installation and Repair
Gas leak repair
Short answer
If you smell gas, leave the building first and call your gas utility or 911 from outside; don't switch lights or appliances on or off. The utility makes the site safe and may shut off the meter. A licensed plumber or gas fitter then finds the leaking pipe, fitting or connector, repairs it, and pressure-tests the system before the utility or the plumber restores gas and relights appliances.
Updated · Prepared by the Plumb Right Now editorial team
Gas Leak Repair at a glance
- First step
- Leave, then call the gas utility or 911 from outside. See smell gas in the house.
- Common leak points
- Flexible appliance connectors, threaded joints, valves and corroded steel pipe.
- Repairs are tested
- The system is pressure-tested before gas is turned back on.
- Permits
- Many jurisdictions require a permit and inspection for gas piping work.
Before any repair: make it safe
- Leave the house with everyone, including pets. Don't stop to open windows if the smell is strong.
- Don't use light switches, phones, appliances, doorbells or anything that can spark inside.
- Call the gas utility's emergency line or 911 once you're outside and well away from the building.
- Don't go back in until the utility or fire department says it's safe.
A faint smell near one appliance still warrants a call to the utility; they check for free in most areas.
How the leak is found
After the utility has made the site safe, the plumber or gas fitter checks the piping from the meter to each appliance. A leak-detection solution bubbles at small leaks on joints and valves, an electronic detector picks up gas in the air around concealed pipe, and a pressure test on the isolated system shows whether it holds pressure at all.
The most common culprits are flexible connectors behind ranges, dryers and water heaters, threaded joints that have loosened, worn shutoff valves, and steel pipe corroded where it passes through damp crawlspaces or exterior walls.
Repair or replace?
| Leak source | Usual repair |
|---|---|
| Old or kinked appliance connector | Replace the connector and its shutoff valve |
| Loose or failed threaded joint | Disassemble, re-seal with gas-rated compound and re-test |
| Leaking shutoff valve | Replace the valve |
| Corroded steel pipe | Replace the corroded section, or reroute if corrosion is widespread |
| Damaged flexible gas tubing (CSST) | Replace the damaged run with approved fittings; confirm bonding where required |
Getting gas service back
Pressure test
The repaired system is pressurized and watched to confirm it holds.
Inspection, where required
Many areas require a permit and inspection for gas piping repairs.
Restore and relight
The utility or the plumber turns gas back on, purges lines and relights pilots, then checks each appliance.
Other urgent plumbing services
Common questions
Who should I call first if I smell gas?
Your gas utility's emergency line or 911, from outside the building. They make it safe before any repair.
Can a plumber repair a gas leak?
Yes, a plumber or gas fitter licensed for gas work in your state repairs leaks on the piping inside your property.
Can a gas leak be repaired without shutting off gas to the whole house?
Sometimes. If the leak is on one appliance branch, that branch can often be isolated at its shutoff valve; if the source is unknown or near the meter, the whole system stays off until it's found and tested.
How do plumbers find a gas leak?
With leak-detection solution on joints, an electronic gas detector and a pressure test on the isolated piping.
What usually causes a gas leak at an appliance?
An old, kinked or loose flexible connector, or a worn shutoff valve behind the appliance.
Is it safe to tighten a leaking gas fitting myself?
No. Leave, call the utility and have a licensed professional repair and test it.
Will my gas be turned off during the repair?
Usually, at least to the affected section, and it stays off until the system passes a pressure test.
Do gas line repairs need a permit?
Often. Many jurisdictions require a permit and inspection for gas piping work; the plumber can tell you what applies.
What does a rotten egg smell mean near my water heater?
It may be gas, which has an added odorant; treat it as a leak. A sulfur smell only from hot water is a different problem: see rotten egg smell in hot water.
Should I get a carbon monoxide alarm after a gas repair?
Yes, if you don't have one; CO alarms are a separate safety layer for any home with gas appliances.