Image courtesy of US Geological Survey (www.usgs.gov)
The shaking of an earthquake can topple a standing water heater, causing water damage, rupturing the gas line, and possibly sparking a fire. That’s why California law requires homeowners to secure their water heaters.
I’ve poked my nose into a lot of basements and garages, and what I’ve seen can be scary. It is not sufficient to strap a water heater with thin metal “plumber’s tape” when it stands against a straight wall. Though it looks superficially like strapping tape, plumber’s tape may not be sufficient to withstand the weight and force of a water heater during an earthquake. This was a lesson learned the hard way during the 1989 Loma Prieta earthquake, when many water heaters broke through their strapping.
In my own house, the proper tape was in place, but thanks to an awkward location, the bolts were not actually in place to secure the water heater.
So let’s review:
- Use flexible connectors to attach the water heater to the gas line. That bit of flex makes a rupture much less likely.
- Secure the water heater with two straps, one near the top and another near the bottom. (Pre-1989 standards called for just one strap near the top or in the middle.)
- The straps must be anchored to studs or masonry.
- If the water heater is in the garage, it must be raised off the floor. This is easily accomplished with a metal water heater stand.
Your reward for making sure your water heater is properly secured? In case of a major earthquake, your home will more likely be habitable, safe from water or fire damage. Even better, an 80-gallon water heater can supply a family of four with a 20-day supply of drinking water. And that’s a lot of preparation.