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Have Crawl Space Flood Vents? Here’s What You Should Know

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Think about the last time floods swept across your Florida neighborhood wreaking havoc and leaving people homeless. Whether it was a few years ago or a decade, the effects may still be visible and memories fresh. Here’s the sad part. Some people lost their homes simply because their foundation walls didn’t have flood vents.

Fast forward to 2020 and imagine if such an unfortunate thing would happen again. Will your home stand, or will you join the list of homeowners whose houses get swept away by annual floods? Trust us when we say you don’t want to find yourself in a similar scenario.

Flood Vent Basics

You can install flood vents on foundation walls, garage door walls, enclosed walls, and the crawl space. How many flood vents you will install depends on the size and type of vents you need. Each enclosed space must have at least two openings. Usually, the ratio is one square inch of opening on your walls for every square foot of your home. If you have 1,500 square feet of crawl space, you will need an opening that’s 1,500 square inches.

If there are multiple areas within the exterior foundation walls, each of them should have two openings as well. They should all be below the flood level so they can work effectively. The lower section ought to be no more than one foot above the exterior grade or the interior grade, whichever is higher.

Anytime it floods, water pressure on the inside and outside needs to equalize fast enough. Otherwise, your doors and windows could blow out. This pressure can also weaken your foundation, rendering it unsafe for habitation. Many studies show that homes with proper vents survive floods while those without tend to collapse.

Benefits of Flood Vents

Besides controlling floods, these devices help you meet building code and fulfill FEMA plus National Flood Insurance Program requirements. Flood vents for crawl spaces come with insulation and weather stripping, which enhance the energy efficiency of your crawl space, and home at large. You can use them in your newly constructed home or as a retrofit. Since they’re made from stainless steel, they’re resistant to corrosion. Various sizes are available to fit standard crawl space vent openings.

If your home sits on a floodplain, you may have to take flood insurance to protect your home. Insurance policies rate homes without flood openings severely. And this results in higher premiums. So, adding proper flood openings can make you compliant and reduce your flood insurance costs.

Signs of a Damaged Flood Vent

Your once functional and sturdy flood vents may fall apart because of wear and tear or other reasons. Telltale signs that something is wrong include cracks at the top of the vent, cracks between the foundation and the vent, holes in the screen, and damaged foam. Don’t forget to check the clips as they could have failed as well.

Maintaining Your Flood Vents

Food vents are usually installed on the exterior wall of the crawl space, a place where most people ignore or overlook during home maintenance. For this reason, they can fail during floods and encourage floods to destroy the foundation. Ensure no grates, grilles, louvers, screens or other devices obstruct or hinder the automatic flow of floodwater within the enclosed space. We strongly recommend that you wash the vents at least twice a year with fresh, clean water.

When Should I Repair My Flood Vents?

Spring and summer are exciting times when everybody wants to go outdoors and have fun. But they’re also seasons that are marked by heavy downpours that can inflict serious damage to your foundation.

Your biggest concern should be the ferocious floods that sweep across neighborhoods, leaving a trail of destruction. Before the wet season and hurricane season sets in, check the crawl space vents as well as other vents on the exterior of your foundation walls. Ask your foundation repair contractor to retrofit any that are damaged.

Don’t take chances with the rains as you never know what surprises the weather could throw your way. Be sure, smart, and safe by using flood vents. Schedule a free flood vent inspection and quote with our experts at Alpha Foundations, servicing homes throughout Florida.

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