How Much Does an Earthquake Retrofit Cost? [2024 Data]

Normal range: $3,489 - $8,676

Earthquake retrofit costs range from $3,489 to $8,676, depending on the square footage and labor costs.

How we get this data
San Francisco row homes in the morning
Photo: Andy Koneiczny / Adobe Stock
Lauren Bongard
Written by Lauren Bongard
Contributing Writer
Updated August 26, 2024
San Francisco row homes in the morning
Photo: Andy Koneiczny / Adobe Stock

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.

See the price range for earthquake retrofit in
your area
How we get this data
Normal range for U.S.
$3,489 - $8,676
  • Average
  • $6,082
  • Low end
  • $800
  • high end
  • $15,000
LOWHIGH

Costs by Earthquake Retrofitting Method

8 foundation seismic retrofitting elements, including wood blocking, anchor bolts, and framing clips

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.

Foundation Bolting

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

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

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.

Crawl Space Shear Wall Bracing

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 MethodAverage 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 Retrofitting Cost per Square Foot

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.

Structural Engineering Cost

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.

Cost by Location 

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:

LocationAverage Cost
Los Angeles$3,500–$6,600
Portland, Oregon$2,800–$6,300
San Francisco$5,000–$8,000
Seattle$5,800–$12,800

Additional Cost Factors 

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.

Type of Foundation

Home being built on concrete foundation
Photo: Brizmaker / Adobe Stock

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 FoundationAverage 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

Type of Home

Earthquake retrofitting might be more expensive for houses most vulnerable to earthquake damage, such as soft-story structures or homes on hills.

Home TypeAverage Cost
Hillside$5,000–$10,000
Manufactured$5,000–$15,000
Mobile$3,000–$25,000
Soft story$10,000–$350,000

Hillside Home

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.

Manufactured Home

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 Home

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

Soft Story

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.

How Much Does It Cost to Do an Earthquake Retrofit Yourself?

Man purchasing plywood to retrofit
Photo: Sergey Ryzhov / Adobe Stock

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.

How Angi Gets Its Cost Data

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. 

Want to help us improve our cost data? Send us a recent project quote to costquotes@angi.com. Quotes and personal information will not be shared publicly.

Frequently Asked Questions

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.

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Learn more about our contributor
Lauren Bongard
Written by Lauren Bongard
Contributing Writer
Lauren is a full-time writer and editor, focusing on home improvement and construction. She enjoys combining her interest in renovating homes with real-life tips that can make the job easier. Her personal style emphasizes sustainability, retaining original character, revealing hidden beauty, and a love for all things old.
Lauren is a full-time writer and editor, focusing on home improvement and construction. She enjoys combining her interest in renovating homes with real-life tips that can make the job easier. Her personal style emphasizes sustainability, retaining original character, revealing hidden beauty, and a love for all things old.
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