Welcome to the third week of our "Building for Resilience" series. This week, we turn our attention to a pressing concern for many homeowners: flood resistance.

Floods can cause significant damage, disrupt lives, and lead to costly repairs. Even in areas like the Texas Panhandle, where the wettest month typically sees 9 days of rain per year, flooding can become a serious problem.

Implementing flood-resistant building techniques is crucial for ensuring that homes can withstand rising waters, minimize property damage, and protect both the home and its inhabitants. In this blog post, we'll explore various strategies and technologies that enhance a home's resilience against flooding, improving your home’s security and your peace of mind.

The True Dangers of Home Flooding

Flooding can occur due to various reasons, including heavy rainfall, storm surges, overflowing rivers, and inadequate drainage systems. Understanding the specific risks in your area is the first step toward practical flood-resistant construction.

According to research, approximately 6 million Texans (about 20% of the population) live in an area at risk of flooding. Texas was one of the top states for flood insurance claims between 1971-2021, along with Louisiana, Florida, New York, and New Jersey. Hurricane Katrina alone cost homeowners $22.1 billion in flood damage.

Flood risks vary from state to state and neighborhood to neighborhood. When you’re preparing to purchase a new home or build a home from scratch, you should always consult local flood maps, historical data, and municipal planning resources to assess the flood risk accurately.

4 Steps to Flood-Proof Your New Construction or Existing Home

Homebuilders can implement proactive strategies during the construction process to flood-proof new construction. These simple steps can reduce the risk of flood damage, even in unexpected summer downpours.

Similarly, while you can’t always choose where your existing home is built, there are actions you can take to ensure an existing home is protected.

1. Elevating the Structure & Essential Utilities

One of the most effective ways to protect a home from flooding is to elevate it above the potential flood level. This can be achieved through several methods:

Pier and Beam Construction

Homes built on piers or stilts are elevated above the ground, allowing floodwaters to pass underneath without damaging the living space. When made with the right high-quality materials, piers and beams can be a permanent way to improve a home’s stability as well as provide a barrier to floodwaters.

Raised Foundations

For new homes, raising the foundation to a higher level than the surrounding ground can provide significant protection against flooding. This can involve using fill material to raise the entire site or constructing the home on an elevated concrete slab.

When raising foundations onto concrete blocks, using two 8x16 blocks rather than one 8x8 block will provide maximum stability and durability for the home. This technique can support 5-20x the weight of a single block support.

Retrofitting Existing Homes

For existing structures, retrofitting involves raising the house onto a higher foundation or stilts. While this can be an expensive and complex process, it significantly reduces flood risk and can be a worthwhile investment in high-risk areas.

Protecting Utilities

Placing utilities such as electrical panels, HVAC systems, and water heaters above the potential flood level can prevent damage and ensure that these critical systems remain operational during a flood.

2. Choosing Flood-Resistant Materials

Many traditional materials aren’t built to withstand large amounts of water. When building a home, the area below the base flood elevation needs to be made from flood-resistant materials. 

According to the National Flood Insurance Program, flood-resistant materials are able to withstand at least 72 hours of water exposure without significant damage. These materials may require the occasional cosmetic upkeep, but they won’t need to be replaced or removed due to flood damage alone. Materials that aren’t considered flood-resistant include:

• Water soluble adhesives

• Wood or paper products

• Sheet-type floor coverings like linoleum and rubber tiles

• Wallpaper

• Any materials that absorb or retain water

Materials such as concrete, steel, and pressure-treated wood are more resistant to water damage than traditional building materials. Using these materials for foundations, walls, and structural elements can enhance a home's resilience.

Materials in class 5, the top tier for water resistance, include:

• Glazed brick or clay tile

• Cast stone in waterproof mortar

• Fiber-cement board

• Concrete blocks

• Marine grade plywood

• Recycled plastic lumber

• Steel

• Decay-resistant hardwood

• Glass

You’ll also need to ensure that all hardware, fasteners, and connectors are flood-resistant. Stainless or galvanized steel is the best option for these materials.

3. Waterproofing and Sealing

Preventing water from entering the home is another critical aspect of flood-resistant construction. This involves using materials and techniques designed to keep water out:

Waterproof Membranes

Applying waterproof membranes to the exterior walls and foundation can create a barrier that prevents water from seeping into the home. These membranes are typically made of rubber, plastic, or asphalt. Ideally, you’ll want to place the waterproof membrane along the below-grade walls.

Positive-side waterproofing, or applying a waterproof layer between the substrate and the elements, is the best way to keep water out and reduce water pressure on the membrane. You’ll need to wait until the area is dry, and if your substrate is concrete, ensure the curing period is long enough before installation.

Sealants and Coatings

Sealants and coatings on walls, floors, and foundations can help create a waterproof barrier. These products are designed to fill cracks and gaps, preventing water intrusion. You’ll want to seal wooden decks, stairs, and fencing to avoid water damage. Concrete and other porous materials also need to be sealed to prevent cracks, discoloration, chipping, and salt buildup.

Flood Vents

Installing flood vents in the foundation allows water to flow through the crawlspace or basement, reducing pressure on the walls and foundation. This can help prevent structural damage during a flood.

FEMA-compliant flood vents are made waterproof to resist rust and rot. In some situations, they can lower your insurance premiums. Today, they come in a variety of shapes and styles to blend effortlessly with your home design.

4. Landscaping and Site Design

The design of the site and landscaping around the home can also play a significant role in flood prevention:

Grading and Drainage

Proper grading ensures that water flows away from the home, reducing the risk of flooding. Installing drainage systems, such as French drains, can help manage water flow and prevent accumulation near the foundation.

For proper grading, the ground should be one inch lower for every foot that you move away from the house for the first 10 feet around the house. This downward slope allows water to drain away from your foundation naturally. You’ll want at least 4 inches of your foundation to show above the soil. The top recommended soil for grading is screened topsoil containing clay.

Rainbarrels placed under your drains allow you to collect runoff to then use for gardening. Similarly, installing sump pumps and drainage systems in basements and crawlspaces can help remove water quickly, reducing the risk of damage and mold growth.

Retention Ponds and Swales

Creating retention ponds or swales on the property can help to manage stormwater runoff. These features collect and slowly release water, reducing the risk of flooding.

You can use downspout extenders, catch basins with PVC pipes, and yard drains to carry runoff to the retention pond underground without creating mini-ravines in your front yard.

Permeable Surfaces

Using permeable materials for driveways, walkways, and patios allows water to infiltrate the ground rather than running off. This reduces the risk of surface flooding and helps to recharge groundwater.

For example, concrete and asphalt will dry quickly while keeping your vehicle out of the water.

Protect Your Home, Family, & Furniture from Flood Damage

Flood-resistant building techniques are essential for safeguarding homes against the increasing threat of flooding. By elevating structures, waterproofing, and using durable materials, homeowners can significantly reduce the risk of flood damage.

As we continue our series on building for resilience, stay tuned for more insights and strategies to protect your home against the challenges of an ever-changing environment. Thank you for joining us on this journey towards creating homes that are not only beautiful and efficient but also resilient and secure.

At Caprock Design + Build, we incorporate thoughtful site design, construction best practices, and landscaping into each home we build, ensuring your home can withstand the worst of nature's fury.  If you’re dreaming of building your forever home in the Texas Panhandle region, or you want to weather-proof your existing home, give us a call now.