Before Anything Else: Do Not Press the Button
If water reached the garage floor, wait until the floor is dry and the power to the garage circuit has been checked before you run the opener. Standing water beside a 120 volt outlet is the real hazard, and an opener that pulls against a door swollen or jammed by debris can strip its own gear in a single attempt.
The opener head unit is mounted on the ceiling, so unless the water was several feet deep it stayed dry and is usually fine. The low items are the problem. The photo-eye sensors, the sensor wiring stapled along the wall, the wall control button and any outlet near the floor are the parts that were actually under water.
If you need the door open before all this is sorted, do it by hand. With the door fully closed, pull the red release cord to disconnect the opener, look up to confirm the spring above the door is intact with no gap in the coil, then lift. Never pull the release with the door open, because a door with a broken spring will drop.
What Water Does to Each Part of the Door
Parts sort into three piles: those that dry out and carry on, those that dry out and then corrode, and those that are finished the moment they go under.
| Part | Usually dries out? | Replace when |
|---|---|---|
| Photo-eye sensors, mounted within 6 inches of the floor | Sometimes, if only splashed | They were submerged, the lens is fogged inside, or a light flickers after drying |
| Low-voltage sensor wiring and staples | Often | Insulation is cracked, or green corrosion shows at the terminals |
| Wall control button | Rarely if it went under | Any submersion; it is inexpensive |
| Opener head unit on the ceiling | Untouched in most floods | Only if water reached the ceiling |
| Bottom weather seal and retainer | Yes, but it holds silt | Torn, flattened, or the retainer has corroded |
| Bottom section, steel | Dries; rust starts within weeks | Bubbling paint at the bottom rail or any perforation |
| Bottom section, wood | Slowly, and it swells | It warps, delaminates or no longer seals |
| Insulated section with foam core | Foam does not soak, but the skin gap holds water | Skins separating or crackling when pressed |
| Bottom brackets and cable ends | Dry, then corrode fast | Frayed strands or a pitted bracket in the months that follow |
| Torsion springs on the shaft | Usually above the water line | Only if submerged; then watch for heavy scale |
| Rollers and hinges | Dry; open steel bearings rust | Squealing, grinding or stiff pivots once dry |
Photo Eyes and Low Wiring After a Flood
Photo-eye sensors have been required on residential openers since 1993 under UL 325, and the same standard puts them no more than 6 inches above the floor. That placement makes them the first electrical component to go under in any flood. If the door refuses to close, or the opener light flashes when you press the button, look here first.
Unplug the opener, dry both eyes and their connections, and plug it back in. Each eye has a small indicator light. Both should be steady. A dark or flickering light after 48 hours of drying means that eye or its wiring is done. Sensors are replaced as a matched pair, and the work falls inside our normal opener repair band of about $125 to $350 depending on what else the water reached.
The wiring deserves its own look. The thin two-conductor cable runs along the baseboard from each eye back to the opener, often stapled to the drywall. Water wicks up under the insulation at every staple and every splice, and the corrosion at the terminals on the opener head shows up weeks later as a door that reverses at random. If the wire was under water, replacing it is cheaper than chasing intermittent faults. Sun glare on the eyes produces similar symptoms, and our guide to garage door sensors and afternoon sun explains how to tell them apart.
The Bottom Section, Seal and Retainer
Pull the bottom seal out of its retainer within 48 hours, hose the silt out, let both dry, and refit or replace the seal. Silt trapped in the retainer holds water against the bottom rail, and on a steel door that is where rust-through starts. A new seal is inexpensive; a rusted bottom section is a $300 to $700 panel.
On a steel door, wipe the inside face of the bottom section dry and look along the bottom rail for water still weeping out of the seam. Insulated sections can hold water between the foam and the skin for days. Prop the door open on a dry afternoon and let it drain. Any bubbling in the paint along that rail over the next month is rust starting from inside, and it is worth treating early.
Wood and wood-composite doors are a different case. The bottom rail swells, the panels can delaminate, and a door that has been standing in water for more than a day frequently never seals properly again. Give it a week to dry with the door open, then judge it. If the rail has gone soft, the section is finished.
Cables, Bottom Brackets and Springs After Standing Water
The bottom brackets bolt to the lowest corners of the door, and the lift cables loop through them, so both spent the flood in muddy water. Steel wire rope holds silt between its strands, and it will look fine for a few weeks and then start throwing whiskers. Inspect the last few inches of each cable above the bracket at two weeks and again at two months. Fraying, rust bloom or a kink means replacing both cables, which runs about $150 to $300 as a pair. Our cable repair page covers what that visit involves.
The torsion springs sit above the door on the shaft, seven feet or more off the floor, and in most floods they stay dry. If water did reach them, they will show heavy scale within weeks and should be lubricated immediately and watched. Extension springs mounted along the horizontal tracks are also usually above the water line.
Water in the garage and a door you are not sure about?
We will check the sensors, seal, section, brackets and cables in one visit and tell you what can wait.
Insurance, Photos and Paperwork
Before you clean anything, photograph the water line on the door, the sensors, the wall control and the floor, and keep the ruined seal and any failed parts until the claim is settled. Water that rose from the ground is generally a flood policy matter and sits outside a standard homeowners policy, while rain that was driven in through a damaged door is usually treated as storm damage. Policy wording varies, so confirm with your own agent rather than assuming.
Why Sugar Land Garages Flood the Way They Do
Most of the city sits behind levee improvement district levees along the Brazos, so river water reaching a garage is rare. What we see far more often is street flooding after intense rain, when the storm drains cannot keep up and water backs across a driveway and under the door. Garage floors on slab-on-grade homes sit only inches above the driveway, which is why an inch or two of street water becomes an inch or two in the garage.
Harvey in August 2017 dropped well over 30 inches of rain on parts of Fort Bend County and put water in garages that had never flooded before. Properties along Oyster Creek that sit inside the FEMA-mapped floodplain see it more often. Either way, the damage pattern on the door is the same: sensors, seal, bottom section, brackets and cables, in that order.
The good news is that a door caught early rarely needs replacing. Dry it, treat the steel, replace the electrics that went under, and keep an eye on the cables. To get ahead of the next storm season, read our guide to preparing a garage door for hurricane season, and for what corrosion does to hardware over the following year, see rust on garage door hardware in Gulf Coast humidity. When you would rather have all of it checked in one visit, our page on garage door repair in Sugar Land, TX explains how we work and what things cost.