In the Pacific Northwest, earthquakes are a serious risk. These natural disasters can cause thousands of dollars in damage and come at unexpected times. All homeowners in this area surely have a lurking fear of “the big one”, but are your homes properly prepared for the next earthquake?
Earthquake preventative measures have improved dramatically in the construction industry in previous decades, but there are still some weaknesses to pay attention to, especially in homes built before 1995. One of the major features susceptible to damage during an earthquake is the water heater. And in many older homes, water heaters are not properly secured to sustain an earthquake.
Why the water heater?
Historically, water heaters were typically secured using a single strap of plumber’s tape. After the 1994 Northridge earthquake in California, experts learned that the current recommendation wasn’t sufficient, and the standard for water heater strapping was modified.
In addition to new strapping techniques, Steve Gemmell of Earthquake Tech says that “installing seismically activated gas shut off valves has become standard practice…” in construction of new homes. “These are both great ways to keep your rentals intact, preventing fire and water damage which can end up totaling your property if not costing thousands in damage.”
In areas that may be subject to earthquakes, including much of the real estate along the West Coast, seismic straps for water heaters are a requirement. In many other states, seismic straps are also recommended. Of course, legal jurisdiction varies state to state, so always be aware of the laws in your region and keep your property up to code.
What California law requires in 2026
In Washington and California, seismic water heater straps are required by law. This includes securing the top and bottom of the tank using heavy-gauge metal strapping. In Oregon, the Plumbing Specialty Code (OPSC) requires water heaters to be strapped or anchored in seismic categories. The Uniform Plumbing code requires that water heaters be strapped on both the top one-third and lower one-third of the tank, however some state’s architects and building jurisdictions require a third or fourth strap for tanks up to 100 gallons in volume. If you’re not sure of the requirement in your area, call the local building department.
- Health & Safety Code §19211: every new, replacement, and existing residential water heater must be braced, anchored, or strapped against earthquake displacement.
- Two strapping points: one within the upper third of the tank and one within the lower third (California Plumbing Code §507.2).
- Lower strap placement: at least 4 inches above the thermostat and gas control valve, so a strap can’t crack the controls during a quake.
- Strap material: minimum 22-gauge metal, at least 5/8-inch wide, or plumber’s tape that fully encircles the tank.
- Straps by tank size: up to 52 gallons needs 2 straps, a 75-gallon tank needs 3, a 100-gallon tank needs 4.
- Point of sale: the seller must certify in writing to the buyer that the water heater is strapped to code before a home changes hands.
How to strap a water heater
- Shut off the gas or the power to the heater before you start.
- Wrap the upper strap around the top third of the tank and the lower strap around the bottom third, keeping the lower one at least four inches above the gas controls.
- Pull each strap tight so there is no gap between the tank and the wall behind it.
- Anchor both ends of every strap into wall studs with lag screws, not just into drywall.
- Where plumber’s tape is used, run it all the way around the tank and fasten it to framing at each end.
- Fit flexible connectors on the gas and water lines so the tank can shift a little without snapping a rigid pipe.
- If the tank stands in an open alcove or garage, add blocking behind it to keep it from rocking.
What does it cost?
Strapping and bracing a water heater typically costs between $150 and $300 to have done professionally, or about $20 to $40 for a do-it-yourself kit, depending on the size of the heater and the residence. While this may seem unnecessary if your water heater has remained unstrapped for many years, it is a price well worth paying to protect your home from hundreds or thousands of dollars in damage in the event of an earthquake.
Frequently Asked Questions
Is water heater strapping required in California?
Yes. In California, seismic water heater straps are required by law under Health and Safety Code section 19211, which covers every new, replacement, and existing residential water heater. The tank must be braced, anchored, or strapped against earthquake displacement, and before a home changes hands the seller must certify in writing to the buyer that it is strapped to code.
How many straps does a water heater need?
A standard tank needs at least two straps, one within the upper third of the tank and one within the lower third. Larger tanks need more: a 75-gallon tank needs three straps and a 100-gallon tank needs four. Keep the lower strap at least four inches above the thermostat and gas control valve so it can’t crack the controls.
How much does it cost to strap a water heater?
Strapping and bracing a water heater typically costs between $150 and $300 to have done professionally, or about $20 to $40 for a do-it-yourself kit. The exact price depends on the size of the heater and the residence. It is a price well worth paying to protect your home from thousands of dollars in earthquake damage.