Earthquake retrofit costs range from $3,489 to $8,676, depending on the square footage and labor costs.
If you live in an earthquake-prone area, you need to ensure your home is retrofitted to withstand the shaking. Without an earthquake retrofit, your property and, more importantly, your family’s lives can be in danger. Expect to invest an average of $6,082, with a range between $3,489 and $8,676, on earthquake retrofit costs. You can estimate the cost by size at $3 to $7 per square foot, including labor, as you plan your project.
Some methods, like bolting, are less expensive ways to secure your home during an earthquake. Shear wall reinforcements require more materials, which increases the costs. Depending on the style of your home, you may require multiple retrofitting techniques for earthquake resistance.
This popular type of earthquake retrofit involves bolting your home to its foundation to prevent it from sliding off during an earthquake. Foundation bolting costs about $500 to $3,000, including labor.
Crawl space wall bolting is the process of bolting or anchoring crawl space walls—the short stud walls between a foundation and floor in some homes—to the floor above. This process helps prevent these walls from shifting as the house shakes. Crawl space wall bolting costs an average of $1,000 to $3,000 and is popular for homes with brick foundations or crawl spaces.
Anchoring a mudsill is similar to bolting a crawl space wall. With this technique, professionals bolt the mudsill (the first layer of wood above a foundation wall that is the base of framing). The bolts go through the mudsill and into the crawl space wall, and the cost is $1,000 to $3,000.
This method involves bracing the crawl space wall with plywood, steel grates, or 2-by-4 blocking to prevent it from shifting during an earthquake. Expect to spend around $1,000 to $2,500 for this retrofitting technique.
| Earthquake Retrofitting Method | Average Cost |
|---|---|
| Foundation bolting | $500–$3,000 |
| Crawl space wall bolting | $1,000–$3,000 |
| Anchoring mudsill | $1,000–$3,000 |
| Crawl space wall bracing | $1,000–$2,500 |
Earthquake retrofits cost anywhere from $500 to $10,000, although the average range is $3,489 to $8,676. In terms of square footage, you’ll spend about $3 to $7 per square foot for a retrofit, including labor.
Without labor, costs are around $1 to $3 per square foot, but hiring a professional is best to ensure your home is properly secured in the event of an earthquake.
Most seismic retrofitting companies have structural engineers on staff who will evaluate your home’s condition and suggest updates to make it safer during an earthquake. The cost of this survey is part of the initial bid your contractors will give you, but ask to be sure it’s included.
If it’s not, consider hiring a separate structural engineer to weigh in on your earthquake retrofitting needs before you begin. This is particularly important if your home is older or has existing structural problems, such as foundation issues or large open spaces on the main floor.
The cost to hire a structural engineer varies by location and project type. Plan to pay $70 to $250 per hour or between $400 and $1,500 for an inspection by a structural engineer. You’ll pay more for soil assessments, plans, designs, and project labor if you need more than a basic inspection.
Earthquake retrofits vary based on location. Costs are higher in Northern California and the northern part of the West Coast compared to Southern California because of home styles and labor costs. Here’s the average range of earthquake fitting by city:
| Location | Average Cost |
|---|---|
| Los Angeles | $3,500–$6,600 |
| Portland, Oregon | $2,800–$6,300 |
| San Francisco | $5,000–$8,000 |
| Seattle | $5,800–$12,800 |
Now that you know the seismic retrofit costs you can expect by method, square footage, and location, let’s look at how your home’s foundation and the type of home can also impact the price. These details can significantly affect project fees, so factor them into your expected budget if they apply to your home.
The cost of retrofitting your home for an earthquake can depend on the foundation. Bolting your home to a slab foundation is a relatively easy, inexpensive retrofit. On the other hand, dealing with a brick foundation can be a costly project, as brick is easily damaged in earthquakes.
Here are the average ranges for earthquake retrofitting by type of foundation:
| Type of Foundation | Average Cost Range |
|---|---|
| Basement | $3,000–$5,000 |
| Brick | $2,000–$10,000 |
| Footing stem wall | $3,000–$7,000 |
| Wood | $5,000–$10,000 |
| Post and pier | $3,000–$10,000 |
| Slab | $500–$3,000 |
Earthquake retrofitting might be more expensive for houses most vulnerable to earthquake damage, such as soft-story structures or homes on hills.
| Home Type | Average Cost |
|---|---|
| Hillside | $5,000–$10,000 |
| Manufactured | $5,000–$15,000 |
| Mobile | $3,000–$25,000 |
| Soft story | $10,000–$350,000 |
Having a home on a hill can offer privacy and scenic views but also puts you at risk of earthquake damage. These homes tend to have weaker lateral support and require additional foundational and wall anchoring, bringing costs to $5,000 to $10,000 to retrofit.
Installing a new foundation for a manufactured home costs around $5,000 to $15,000, depending on the size of the home. The retrofit to add a full basement to a manufactured home will cost $50,000 to $150,000.
Mobile homes will require an earthquake-resistant bracing system, and the cost varies with the type of system.
Primary support column: $3,000–$9,000
Tie-down straps: $2,000–$5,000
New slab foundation: $5,000–$25,000
A soft story is a structure with multiple stories and a large opening where a structural or shear wall would normally go. It's common in apartment buildings and homes with a second story above the garage.
Soft-story home: Retrofitting a soft story in a standard, single-family home could cost $10,000 to $80,000.
Apartment complex: For larger, multi-unit buildings, the property owner can expect to spend $80,000 to $350,000 for earthquake retrofitting.
Earthquake retrofitting requires professional expertise, and attempting it without an expert is a huge risk to your safety. Improper retrofitting could cause your home to shift, slide off the foundation, or collapse. If you’re trained in earthquake retrofitting, you could save about 70% in labor. For a $5,000 retrofit with labor, you’d spend about $1,500.
However, don’t risk trying to DIY it if you're not an expert. Hire a licensed, experienced pro instead. If you’re wondering who to hire for earthquake retrofitting, consider seismic retrofit companies or foundation repair contractors near you who have the skills, equipment, and expertise to get the job done right and offer you maximum protection during an earth-shaking event.
Home is the most important place on earth, which is why Angi has helped more than 150 million homeowners transform their houses into homes they adore. To help homeowners with their next project, Angi provides readers with the most accurate cost data and upholds strict editorial standards. We survey real Angi customers about their project costs to develop the pricing data you see, so you can make the best decisions for you and your home. We pair this data with research from reputable sources, including the U.S. Bureau of Labor Statistics, academic journals, market studies, and interviews with industry experts—all to ensure our prices reflect real-world projects.
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An earthquake retrofit is essential for safety in an earthquake-prone area. Without proper retrofitting, your home is at risk of sliding off the foundation, shifting, or collapsing.
You may also require a retrofit if your home was built before 1980, when building codes began requiring reinforcing, bracing, and bolting for new construction. You may not be eligible for insurance to help pay for earthquake-related damages without a retrofit.
A home with proper earthquake retrofitting can sustain minimal damage in earthquakes of up to 7.0 magnitude, although risks are higher based on how close and deep the earthquake is. A home closer to the earthquake epicenter will sustain greater damage, especially if the earthquake is closer to the surface of the Earth, but retrofitting can help minimize the risk of injuries.
You’ll need to consult with your insurance agent to know if earthquake damage is covered under your policy. However, earthquake damage is a separate policy from your homeowners insurance. If you live in an area that frequently gets earthquakes, adding earthquake damage coverage to your homeowners insurance should be a no-brainer, especially considering the damage that earthquakes can do.
Earthquake retrofitting can increase your home value, and therefore, your return on investment. This costly and important project makes your home much safer, which is incredibly valuable, especially for earthquake-prone areas of the country like Alaska and California. Home buyers are often willing to pay extra for homes with important safety upgrades.
