Gas Line Repair
We trace gas leaks with gauges and detectors, repair or replace damaged pipe and fittings, and pressure test the line before your appliances go back on.
See the detailsSeismic gas shutoff valve installation for Los Angeles homes
A broken gas line after a strong quake can feed a fire long before anyone reaches the meter with a wrench. A seismic shutoff valve closes on its own when the ground shakes hard enough.
- Answered 24/7
- From 746 S Broadway
- Pipes, gas & water lines
The short answer
A seismic gas shutoff valve mounts on the house side of your gas meter and closes automatically when it senses strong earthquake shaking. Inside, a steel ball or similar mechanism drops into the gas path and stops the flow. You need one if you want gas cut automatically after a big quake, if a sale or remodel triggers the requirement, or if you can't reach the meter quickly yourself.
What the Northridge earthquake taught LA about gas
The 1994 Northridge earthquake, a magnitude 6.7 shock on January 17, 1994, broke gas lines and tipped water heaters across the San Fernando Valley. Fires started in homes where gas kept flowing through broken connectors after the shaking stopped. That experience is a big part of why automatic shutoff valves became common in Los Angeles.
The idea is simple. Shaking strong enough to break pipe is often strong enough to trip the valve, so gas stops before a cracked fitting can feed a fire. The valve does nothing day to day; it just waits on the riser until the ground moves hard enough to trigger it.
For a homeowner-level walkthrough, our article on how seismic shutoffs work covers what happens after one trips and how to tell a false trip from a real one.
Valve mounting, bracing and placement at the meter
Most residential seismic valves install on the house side of the gas meter, on the piping you own. The valve has to sit level and in the orientation the manufacturer specifies, or the sensing mechanism won't work right. We check it with a level, not by eye.
The riser and valve also need support. An unbraced valve hanging off a meter can flex and leak on its own, which defeats the purpose. We strap the pipe to the wall so the meter, valve and house piping move together. The valve must be a model listed for this use and approved by the jurisdiction.
- Mounted on the customer side of the meter
- Set level in the manufacturer's required orientation
- Riser braced to the structure
- Listed model approved for local use
- Reset access left clear for later
Seismic valve or excess flow valves on each appliance
Some jurisdictions also accept excess flow valves as an alternative. These install at each appliance and close if flow suddenly jumps, which happens when a connector breaks. They protect against a ruptured line at one appliance, but they don't respond to shaking itself and won't catch a small leak.
A meter valve shuts the whole house at once, which is the simplest protection when the goal is earthquake safety. The tradeoff is that a strong but harmless quake also shuts everything off, and someone has to reset it. We'll explain both options and what your city accepts.
Resetting the valve after it trips
When a seismic valve closes, every appliance loses gas. Before reopening anything, walk the house and check for the smell of gas, damaged connectors or a water heater that moved. If you smell gas, leave the building, call SoCalGas or 911 from outside, and wait for them to clear it before anyone resets the valve.
If there is no sign of a leak, the valve can be reset by following the manufacturer's procedure, and every pilot in the house then has to be relit. Many owners would rather call us for that, and we check the piping with a detector before any appliance comes back on. If the shaking damaged a line, our gas leak repair work handles the fix and the pressure test.
Seismic shutoffs in Los Angeles, from the Valley to the harbor
Earthquake risk runs through the whole region, but the Valley carries the clearest memory of gas fires after Northridge. Older homes in Reseda, Northridge and nearby tracts often have water heaters and furnaces piped rigidly, so a valve at the meter adds a real layer of protection. Rules on when a valve is required vary between the City of LA and other cities, so we check before quoting. Pair the valve with properly placed tank straps: two straps, one in the upper third and one in the lower third of the heater.
Warning signs
Reasons to put a seismic shutoff on your meter
- Older home with rigid connectorsHard-piped water heaters and furnaces are more likely to break their gas connection when the house moves in a quake.
- Selling or remodelingSome cities require an automatic gas shutoff when a home is sold or when remodel work reaches a certain value.
- Nobody home much of the dayIf the house sits empty while you work, a valve closes the gas when no one is there to do it by hand.
- Meter is hard to reachA meter behind a locked gate, down a steep side yard or in a crowded utility closet is hard to shut quickly after a quake.
- Hillside or soft-soil lotHomes on slopes or fill soils see more movement in shaking, raising the odds of a broken pipe or fitting.
- Old valve that has trippedA valve that closed in a past quake or got knocked loose needs inspection, resetting or replacement.
On the job
Installing a seismic gas shutoff valve, step by step
- STEP1
Check the meter setup
We look at the meter, riser and nearby piping to confirm there's room for the valve and a sound wall to brace against.
- STEP2
Pull the permit
Inside the City of LA we file with LADBS; elsewhere, with your city's building department.
- STEP3
Shut off and install
With gas off at the meter, we install the listed valve on the house side, level it and brace the riser to the wall.
- STEP4
Leak test the joints
Every new connection is checked with soap solution and a gas detector once the line is pressurized.
- STEP5
Relight and walk through
We relight each appliance and show you where the valve is, what a tripped valve looks like and how resetting works.
Typical pricing
Seismic shutoff valve costs in Los Angeles
The valve itself is a modest part of the price; labor, riser bracing, permit fees and relighting several appliances make up most of it.
| Job | Typical LA range |
|---|---|
| Standard meter-mounted valve, installed and braced | $450 to $950 |
| Valve plus riser modifications for clearance | $800 to $1,600 |
| Reset and relight after a trip, with leak check | $150 to $350 |
| Excess flow valves at several appliances | $400 to $1,100 |
These are typical ranges, not a quote; permit fees, riser condition and the number of appliances to relight change the final total. See every job in our LA price guide.
Questions we hear
Seismic Gas Shutoff Valve questions from LA customers
Will a seismic gas shutoff valve trip from a truck or small quake?
Approved valves are designed to ignore everyday vibration like trucks, slammed doors or minor quakes. They respond to strong, sustained shaking. A valve that trips without a real quake is usually mounted out of level or got bumped, and we can reset and correct it.
Is a seismic shutoff valve required when I sell my LA home?
Some cities in the region require an automatic shutoff device at sale or after major remodels, and the rules and accepted devices differ by jurisdiction. Your escrow paperwork or the local building department will say what applies. We check before installing so the device you get is the one your city accepts.
What should I do if my seismic valve closed but I smell no gas?
Walk the house and look at each appliance connection and the water heater for movement. If everything looks intact and there's no odor, the valve can be reset per the manufacturer's instructions, then every pilot relit. If you're unsure, call us. If you smell gas at any point, leave and call SoCalGas or 911 from outside.
Does a seismic gas shutoff valve need maintenance?
Not much. Check once a year that it's still level, the bracing is tight and nothing is stacked against it. After any noticeable quake, look at the indicator to see whether it tripped. A corroded or damaged body should be replaced.
Coverage
Where we handle seismic gas shutoff valve most
These are the communities that call us for this most often, with their main ZIP codes. The same 24/7 line covers every one of our 68 service areas.
- Los Angeles 90014
- Long Beach 90802
- Santa Clarita 91355
- Glendale 91205
- Pasadena 91101
- Torrance 90503
- Downey 90241
- Burbank 91502
- Reseda 91335
- Sylmar 91342
- Pacoima 91331
- Panorama City 91402
- North Hills 91343
- San Pedro 90731
- Granada Hills 91344
- Inglewood 90301
- El Monte 91731
- West Covina 91790
- Anaheim 92805
- Santa Ana 92701
- Whittier 90601
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See the detailsNeed seismic gas shutoff valve today?
Call the line any hour. A plumber answers, asks what you are seeing and tells you what happens next.