When you decided to build in the Florida Keys, you probably thought about our area’s unmatched natural beauty. Interestingly, the very features that make our islands unforgettable are the same ones that complicate construction. What does it take to successfully build on shifting sands? Today, we’ll dive into the steps you’ll need to take, your foundation options, and the questions we’ve received about this process.
While the Keys may be a vacation destination for many, our weather presents a challenge for homebuilders who want to live on the islands full-time. Houses here have to withstand high winds, storm surges, and hurricane aftereffects like erosion and floodborne debris. That kind of durability requires a foundation made of quality material. Builders achieve long-lasting results by analyzing the composition and load-bearing capacity of the substrate before choosing the correct type of foundation for the project at hand.
If you’re hoping to build your own beach house, start by doing your due diligence. Construction in coastal regions calls for a good deal of preparation. This is especially true in the Keys, where our competitive Rate of Growth Ordinance (ROGO) system requires builders to meet strict timelines. Once you receive a permit, the clock starts ticking — typically, you have just six months to break ground. It’s best to do as much upfront work as possible so that your crews start work immediately.
Your first step should be to request a soil test and a geotechnical report. Coastal Florida’s substrate ranges from fine sand to sandy soil. Each variety requires its own foundation solution. In the testing process, experts will examine the soil structure of your lot, while geotechnical reports provide valuable insights about how you should proceed. These documents will help you decide which foundation is right for your home.
While most inland construction sits on concrete slabs, coastal homes have different requirements. Florida builders adhere to the International Residential Code (IRC), which contains a full chapter on the subject of foundations. The International Code Council has compiled standards for minimum required depth, materials, footing setbacks, and other aspects of the foundation construction process. Crucially, homes built in any flood zone must be elevated above the floor level, protecting the structure from storm surges during hurricane season.
How you elevate your home depends on factors like soil composition, the weight of the building, and the price point of your build. Options range from affordable and shorter-term to nearly permanent. In the Keys, most structures have open foundations, which rest on treated wood pilings, helical piers, concrete pilings, or a pier and beam system.
Treated wood pilings are the supports most people think of — everyone has seen a beach house up on stilts. Rounded wood supports, also called “gun barrel pilings,” tend to hold up better than square timbers, which experience uneven forces during flooding. Regardless of which wooden option you choose, these affordable supports are short-lived; they only last a few decades.
Helical piers work like giant screws, threading into the ground when unstable soil conditions prevent standard foundation options. This installation method makes them more eco-friendly than other options; however, they tend to be costly and might not work for very soft soil.
Concrete pilings may be precast or poured on site; both options offer permanent support that will stand the test of time. Concrete also offers much more strength than any other option — these pilings do not rot over time, and borers cannot damage them. For these reasons, nearly every home constructed in the Keys uses concrete.
A pier and beam system offers the permanence of concrete with an additional feature: girders connecting the piers for additional support. Each pier is anchored in the bedrock. While this approach is more expensive, it offers protection from flooding and unmatched structural integrity.
When weighing your options, remember to get an expert opinion. Work directly with your contractor and local foundation experts to determine which supports are right for your home. Beginning with a strong foundation ensures you’ll enjoy your beach house for years to come.
If you’re building on sand, you need the right materials. We can help. Monroe Concrete is a subsidiary of Charley Toppino & Sons. Our team has provided ready-mix concrete and construction materials to the Florida Keys since 1947. While concrete is our business, service is our passion. Contact us to learn how Monroe Concrete can help you build a solid foundation for your future.