In low-lying and coastal neighborhoods, a heavy rain, a king tide or a tropical storm can put water in the garage before it reaches anywhere else in the house. The garage floor usually sits lower than the living space, and the garage door isn’t designed to be watertight.
That makes the garage a first line of defense, and its door a key part of how your home handles floodwater. The right preparation can reduce the damage to your belongings, your door and opener, and the structure itself.
Here’s what homeowners in flood-prone areas should know, from flood vents to what to check once the water goes down.
Why Garages Take the Hit
A few features of most garages make them especially vulnerable:
- They sit low. Many garage slabs are poured at or near ground level, often a step or more below the house.
- The door isn’t a seal. Garage doors are built to keep out weather, not standing water. Water can come in under the bottom seal and between panels.
- Water pushes hard. When floodwater rises on one side of a wall or door and not the other, the difference in pressure can bend door panels, buckle tracks and even damage walls and foundations.
- Everything sits on the floor. Garages tend to hold boxes, tools, appliances and vehicles, all at the lowest point in the house.
That last point about pressure is the one many homeowners don’t expect. Often it isn’t the water itself that does the most structural damage. It’s the force of water pushing against a closed space.
How Flood Vents Help
Flood vents, sometimes called flood openings, are designed to let floodwater flow into and out of an enclosed space like a garage. That keeps the water level roughly the same inside and outside, which relieves the pressure that can damage walls, foundations and garage doors.
They’re typically installed low on garage walls, close to the floor. Most stay closed to keep out pests and drafts in normal weather, then open automatically when water rises.
A few things to know:
- They may be required. In many designated flood zones, building codes and the National Flood Insurance Program require flood openings in enclosed areas, such as garages, that sit below the base flood elevation. Requirements depend on your flood zone and local rules.
- Sizing matters. The number and size of vents depend on the garage’s square footage and whether the vents are engineered and certified. Your local building department or a qualified installer can tell you what’s needed.
- They can affect insurance. Properly installed flood openings are part of how some homes meet flood-zone requirements, which can affect flood insurance rating. Ask your agent how your home is rated.
- They don’t keep water out. Flood vents let water in on purpose, so belongings still need to be protected.
Before the Water Comes
Ahead of the season
- Store valuables, paperwork and electronics on shelves well off the floor, or in sealed plastic bins
- Keep drains, gutters and downspouts near the garage clear
- Replace a worn bottom seal and check the weatherstripping around the door frame
- Know where your breaker panel is and which breaker controls the garage
- Consider an opener with battery backup, so you can still operate the door if the power goes out before or after a storm
When flooding is forecast
- Move cars to higher ground if you can, and take remotes with you
- Lift anything left on the floor onto shelves, blocks or pallets
- Unplug the opener and any appliances in the garage, or switch off the garage breaker if water is expected to reach outlets
- Don’t block or seal flood vents. They only work if water can move through them
- Close the garage door fully and lock the door into the house
After the Water Recedes
Safety first. Don’t walk into standing water in the garage until the power to that area is off. Floodwater can carry contaminants, so wear boots and gloves during cleanup.
Don’t run the opener yet. Water can damage the motor, the circuit board, the wiring and the safety sensors near the floor. Leave the opener unplugged until it’s been checked. If you need to open the door, use the emergency release with the door fully closed, and stop if it feels unusually heavy.
Look the door over:
- Are any panels bent, bowed or pulling apart?
- Are the tracks straight and still firmly attached?
- Is there mud or debris in the tracks or around the rollers?
- Are the bottom seal and bottom brackets damaged?
- Do the springs and cables look intact?
Watch for rust in the weeks after. Saltwater and brackish floodwater are especially hard on steel. Springs, cables, bottom brackets and hardware that sat in water may corrode faster than usual and should be inspected, and often replaced, even if they look fine at first.
Document everything. Photograph the damage before cleanup or repairs, and keep receipts for insurance.
Building a More Flood-Ready Garage
If you live in a flood-prone area and are replacing your door or remodeling the garage, a few choices make recovery easier:
- Doors and hardware that resist corrosion, such as galvanized steel with a durable finish, aluminum or fiberglass, and corrosion-resistant fasteners
- Composite or vinyl bottom retainers instead of steel ones that sit in water
- Openers mounted high, with wiring and outlets kept well above the floor
- Properly sized and installed flood vents, if your home is in a zone that requires them or you want the added protection
When to call a pro: Bring in a technician after any flood that reached the door, even if it seems to work. Water can damage the opener’s electronics and weaken springs and cables in ways that aren’t obvious right away, and those parts are under heavy tension. A good technician will check the whole system, test the safety features, and tell you honestly what can be repaired and what should be replaced.
No one can stop floodwater, but a prepared garage can make the difference between a messy cleanup and a costly repair.
About the Author
This article was written by the team at Overhead Door Company of Charleston, which installs and repairs residential and commercial garage doors, openers and gates across the South Carolina Lowcountry. The company’s service department works on all brands of overhead doors and offers 24/7 emergency service Contact Us.
