Shake, Rattle, and Hold: Earthquake-Resistant Home Upgrades

Practical upgrades, from anchoring furniture to reinforcing foundations, help your home stay intact when the earth starts to move.

Homeowners can take practical steps to protect their home before an earthquake occurs. weart432/Shutterstock

Long before the ground begins to shake, it’s important to determine whether you live in an earthquake zone. They’re more common than you might think. California grabs the biggest headlines, but did you know that Hawaii and Alaska have major active faults and that even New York City can experience moderate shaking? The Federal Emergency Management Agency website offers some handy earthquake hazard maps that are worth checking out for your area. You can also check local resources to see whether your region offers seismic retrofit grants or loans for homeowners interested in strengthening their homes.

Secure the Interior

Once you get started, one of the easiest things to do, which should be done even in new constructions, is to anchor bookcases and cabinets to the wall. In fact, this is a good idea in non-earthquake-prone areas as well, particularly if one has young children who like to climb. Many earthquake injuries aren’t caused by structural collapse but by falling objects within the home. Use anti-tip kits or safety straps to secure dressers and other large furniture as well, including appliances: washers, dryers, and, in particular, tall appliances such as refrigerators.

Pay special attention to tank-style water heaters, especially gas models that can both cause water damage and start a fire if they tip over. One common fix is to replace rigid water line connections (tankless water heaters included) and rigid gas line connections (to all applicable appliances) with flexible alternatives that are less likely to break in a quake. Check local seismic codes for more details.

TVs and monitors should also be securely mounted to the wall or secured with safety straps that connect to the TV stand, table, or desk they rest upon. Use specialty closed-loop hooks to hang mirrors, art, and framed photos.

Secure displayed breakables with quake putty. (It’s also called museum putty because curators use it to perfectly position antiquities on display.) And don’t forget inexpensive but essential cabinet latches that keep the dishes and other items from flying out.

Keep heavy items such as potted plants or big speakers on the floor or lower shelves, and never, ever put anything heavy above a bed or couch.

Start at the Bottom

A strong foundation is critical. Don’t skimp on the inspection; even a home built to current seismic codes should have a structural engineer look at the foundation at least once per decade to make sure that there are no significant changes in the soil beneath the foundation or the weight distribution of the house.

To bring an older home up to standards, the engineer may recommend several solutions. One is to lift the house and set it back on a seismic code foundation. Base isolation adds a shock-absorbing mechanism underneath the home. A simpler option is mudjacking, the process of pumping a mixture of sand, soil, water, and Portland cement under a concrete slab to lift and level it. Finally, they might recommend underpinning, a process in which the engineer drills and attaches foundation piers next to the home or uses piers drilled directly through a concrete slab to bypass weak soil and anchor the home in bedrock.

Tie-In and Reinforce

Many older homes simply rest on, or are minimally attached to, their concrete foundations and can slide off in a rowdy shake. That’s why, after improving the foundation, if needed, it’s important to bolt the home to the foundation with galvanized earthquake bracing bolts (anchor bolts) with large plate washers to increase their holding power.

Next, have the engineer look at the cripple wall (the wood that frames the crawl space). Cripple wall collapse is a large reason for earthquake-related home failures. Its connection should be reinforced, if needed, with hold-down brackets attached to the foundation for resistance to uplift, shifting, and racking, and it should also be attached to the first-level floor framing joists with seismic code-approved connectors or clips.

Homes built with the floor-framing joists resting directly on the mudsill have a higher resistance to quake-related movement but should still be reinforced with angle iron struts and foundation bolts.

Going Up

To further help resist an earthquake’s lateral forces, add shear walls to weak areas on all levels of the home. These walls are designed to resist lateral forces from wind or earthquakes. There are several ways to do this: You can add plywood or oriented strand board panels to the outside or inside face of vulnerable walls. You can replace key engineer-approved sections of wall with oriented strand board or plywood. Or you can install more expensive but potentially less visually intrusive steel moment frames at critical points.

Next, connect these reinforced walls to the roof and floors on each level with building code-approved metal connectors or brackets. It’s a lot of work, but it can be the difference between sweeping up a few broken trinkets and having to move out of the house during lengthy repairs or potential rebuilding.

Ideally, have the structural engineer come back to ensure that the work, whether DIY or professional, was done properly.

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That’s Not All ...

Protect the home’s electrical system and expensive electronics with quality surge protectors. And make sure that electrical and gas shut-offs are easily accessible.

Guarding Glazing

Window glass flying across the room is a serious danger. Installing laminated glass, which holds together when broken, can help prevent this. If you’d rather not replace your windows, apply safety film to regular glass to help hold any broken glass in the frame. Reinforce window frames and sashes with metal or wood braces and enhanced hardware to keep them from detaching.

Chimneys and Facades

Chimneys can cause significant damage to the home and nearby cars or property if they go down. Buff them up with steel braces, or consider replacing the upper area with lighter materials such as metal, stucco, or lightweight stone veneer panels. Decorative stone facades should be addressed similarly.

Outdoor Prep

Exterior considerations include reinforcing decks and backyard sheds in a similar manner to the home. Also, pool equipment—pumps and filters—should be properly anchored to prevent them from falling over during a quake.