How Much Does It Cost to Build a Seawall? [2024 Data]
Normal range: $15,000 - $60,000
Building a seawall costs $25,000 on average, with a wide range between $10,000 and $100,000, depending on the size and type of seawall.
Have you ever dreamed of living on the coast and wondered: how much does it cost to build a seawall? With an average cost of $25,000 and a range from $15,000 to $60,000, seawalls are an expensive but often necessary project for houses on the water. Expect to pay $100 to $800 per linear foot, with more complex projects sometimes reaching $2,000 per linear foot—or more.
- Average
- $25,000
- Low end
- $10,000
- high end
- $100,000
Cost Breakdown
Types
Homeowners who need a seawall quickly discover this is a project where professional input is a must. The type of seawall you build is more determined by the soil type and water characteristics where the seawall would be installed, so in many ways, you don't have a ton of options when it comes to material.
| Seawall type | Cost per linear foot |
|---|---|
| Vinyl | $200–$600 |
| Steel | $250–$700 |
| Concrete | $200–$800 |
| Wood | $150–$500 |
| Riprap | $70–$200 |
Size
Because seawalls are often priced in linear feet, the size of the wall is one of the largest factors in the total price. The thing about seawalls is they're rarely built in a portion of the property, but rather encircling the entire yard or at least the side that's up against the body of water.
It's not only linear feet that factor in either, but the height of the wall as well. A seawall can be anything from four or five feet high to 15, 20, or more. This depends on your soil type and how deep the water is adjacent to your property, as well as the level of access the crews have when building the seawall.
| Seawall Size in Linear Feet | Cost for Wooden Seawall | Cost for Concrete Seawall |
|---|---|---|
| 100 | $15,000–$50,000 | $20,000–$80,000 |
| 150 | $22,500–$75,000 | $30,000–$120,000 |
| 225 | $33,750–$112,500 | $45,000–$160,000 |
| 300 | $45,000–$150,000 | $60,000–$240,000 |
| 700 | $105,000–$350,000 | $140,000–$560,000 |
Materials
The building materials required when constructing a seawall will vary based on the job site, accessibility, and budget. It’s common—if not required—that large, industrial machinery is used to build the wall. Considering the rental pricing of these machines (over $350 per hour) and the fact you need a license to operate many of them, it makes sense to let a pro perform this work.
Labor
It's hard to calculate the price of labor when larger jobs like this are typically quoted as a single amount. However, expect the hourly rate for the less complicated work to be between $40 and $100 an hour. This hourly price increases almost exponentially once you factor in some of the specialized equipment required–like bulldozers and cranes.
It requires specialized workers to handle that type of equipment, so expect the hourly rate to jump significantly, from $80 to $300 or more per hour. For larger jobs like this, a contractor might not be able to price out the work by the hour because of how complicated the job is, so if that information isn't provided, that's normal. The proposal or contract usually has a set labor price (it will be significantly more than building a boat dock).
Prep
Building a seawall requires a lot more preparation than even some large construction projects. If a seawall fails, its soil can drain into the water and destroy the foundation of a house close to the wall. It's also possible that the water rises beyond the seawall and causes water damage directly.
Doing the proper prep work before engaging in a seawall build is almost as important as the quality of the build itself, and includes:
Site survey with soil condition testing
Obtaining necessary permits
Seawall design (considering water forces and wave dynamics)
Consult with structural engineers
Plan materials logistics and water blockage if required
Develop emergency protocols
Permits
Like any large project, building a seawall must be approved by your local government. Seawall permits are complex so this should be done with a professional. There will likely be several inspections before your municipality approves the permit. This legal permission from the city will cost between $150 and $2,500.
DIY Building a Seawall vs. Hiring a Pro
If there's one important point to drive home here, it's this— don't build a seawall yourself. The amount of money that you would spend on materials would still be quite high. Unless you have experience in land surveying and large-scale construction, you'll probably end up spending more trying to DIY this project and hiring a local fencing professional to fix it than you would have if you had just hired the professional in the first place.
Building a seawall isn't an easy DIY project; it takes serious investment and expertise. There's also the consideration that it requires specialized equipment which will cost you a large amount to rent, but would be wrapped up in the cost of a professional's quote. Unless you have experience with these types of projects you likely won't get past the permit stage.
Tips to Save Money While Building a Seawall
Building a seawall is an expensive process, and while there are some projects where you can cut corners, this isn't one of them. Even for smaller seawalls, there are extreme forces to consider so that the walls are built within the safety and structural parameters an engineer designs.
You could save money if you have clearance to build a wooden seawall and want to use reclaimed materials or if you have the option to choose materials, you could go with something less expensive like vinyl. Seawall construction is complicated but you might be able to save some money if you hire a contractor during a slower period of the year or when they have a gap in their calendar.
Frequently Asked Questions
A seawall protects coastal areas (or your property and house) from water damage and tides. The wall doesn’t just rebound the waves, but it absorbs and dissipates wave energy. For some homes, it’s a requirement, while others may simply want to build closer to the water. You may have more options for calm freshwater, but seawater requires strong material like concrete or riprap.
Other than being extremely expensive, seawalls have the disadvantage of causing adverse ecological impacts. These walls can (and often do) disturb delicate natural ecosystems by redirecting wave energy, which alters marine habitats. Over time, seawalls need to be maintained and in places where the water level is rising, they need to be vertically expanded. This comes at a significant cost to the homeowner.
When seawalls are built correctly, they can last over 30 years, sometimes closer to 100. The construction material matters (steel and wood have a much shorter life span than concrete) but the force of the water, how much debris it carries, whether it's saltwater or freshwater, and other factors all can significantly shorten the life span of a seawall.
The most effective seawall is the one that contains your soil, prevents water damage, and properly redirects wave energy. This is often a concrete wall, but riprap and wood are common alternatives. You need to work with a specialist because hydrodynamics and structural forces are extremely complicated, and while you may think you want a wooden seawall for aesthetic purposes, the only one that might work is concrete. A fencing pro can determine which type you need.
Seawalls don’t require a lot of maintenance, but there are some things you (or a professional) should either check or perform periodically. A visual inspection comes first, followed by cleaning of any plant growth that’s attached itself to the wall. You may need to remove debris if it becomes lodged in the wall. The type of seawall that requires the most maintenance is a wooden wall, and you’ll need to make sure any treatment done to the wood is still working as intended.