(professional retrofitting in only one area)
(larger home with multiple upgrades or issues)
Cost to retrofit a home for earthquake protection varies greatly by region (and even by zip code).
Get free estimates from foundation repair contractors in your city.
Earthquakes can be debilitating disasters and quickly wreak havoc on all kinds of structures. Retrofitting a home for earthquake protection reinforces the home’s structure and makes it more difficult to remove the home from its foundation in an earthquake. Homes that are in higher risk areas for earthquakes according to the U.S. Department of the Interior, U.S. Geological Survey Hazard map (see image) have a greater need for being retrofitted. On average, the cost to retrofit a 1,500 square foot home is $4000-$7000.
The total cost of an earthquake project is largely dependent on the home’s current structural quality and efficiency and location. There are many things that can be done to strengthen and retrofit a house, including the following. Talk to your contractor to find the biggest needs for your home and area.
The most common retrofitting procedure improves a home’s bond with the foundation by adding a piece of wood (called the sill 2 or mudsill 2) to the top of the foundation and reinforcing it with bolts. Bolts that have weakened over time or withstood an earthquake may need to be tightened or replaced after 5-8 years. Expansion bolts are less expensive but more powerful and work well with homes with strong concrete foundations, typically newer houses. Epoxy-set bolts 3 work better with older homes, but they are more expensive. On average, the process costs $2000-$4000.
The cripple wall 4 is the short frame that runs from a home’s foundation to the bottom of the main floor. When an earthquake occurs, the most common damage is from the cripple wall 4 collapsing, which can drop the main floor. Bracing the cripple wall 4 typically includes reinforcing it with plywood 5 in the opposite direction of the original wall, which protects against side-to-side earthquake movement. The process typically costs $1000-$2000.
Also known as floor framing, this process adds a grid underneath ground-level flooring to add additional support. With strengthened side joists and support throughout, the floor is less likely to collapse or move side to side in an earthquake. The average cost is $1000-$2000.
Cost to retrofit a home for earthquake protection varies greatly by region (and even by zip code). To get free estimates from local contractors, please indicate yours.