The short answer
Check the Grading Around Your Garage
Water follows gravity, so the slope of the ground next to your garage matters. If the soil slopes toward the garage, rain runs straight to the foundation and under the door. Look for low spots where puddles form after a storm. You can fix minor grading by adding soil so the ground slopes away from the building, at least 6 inches over 10 feet.
- Look for puddles near the garage walls after rain
- Check if the driveway slopes toward the door
- Inspect the soil for erosion or washout
- See if water pools at the base of the foundation
- Note any cracks in the driveway or apron
Inspect Gutters and Downspouts
Clogged gutters or downspouts can dump water right next to your garage. When rain can't flow through the gutter, it spills over the edge. If the downspout doesn't extend far enough from the foundation, water soaks the soil and can seep into the garage. Check for leaves, debris, and any sagging sections.
Make sure downspouts discharge at least 5 feet from the garage. If they don't, add an extension or a splash block. Also check the gutter slope; it should tilt slightly toward the downspout. If water overflows in heavy rain, the gutter may be undersized for the roof area. A roofer can adjust the system to handle the storm.
- Clear leaves and debris from gutters
- Check downspout extensions are in place
- Look for sagging or loose gutter sections
- Test the flow with a hose to spot leaks
- Consider adding a rain barrel if allowed locally
Look at the Garage Door Seal
The gap under your garage door is a common entry point for water. If the rubber seal at the bottom is worn or missing, rain can blow in or run under the door. Also check the weatherstripping around the door frame. Over time, seals crack and lose their flexibility, especially in hot, dry climates with intense summer storms.
You can replace the bottom seal yourself if it's simple. Look for a threshold or a door sweep that creates a tight fit. For a permanent fix, consider a raised concrete lip or a threshold ramp. If water is coming in through the sides, the door track may need adjusting. A garage door professional can help with a proper seal.
- Run your hand along the bottom seal for gaps
- Check the weatherstripping on the door frame
- Look for daylight under the door when closed
- Test the seal with a flashlight at night
- Replace cracked or brittle rubber seals
Consider Hydrostatic Pressure
If water seeps up through the garage floor, that's a sign of hydrostatic pressure. Heavy rain saturates the soil, and the water table rises. The pressure pushes water through cracks in the concrete slab. This is more common in low-lying areas or where the garage is below grade. You might notice damp spots, efflorescence, or a musty smell.
- Look for damp patches on the garage floor
- Check for white mineral stains on concrete
- Notice a musty odor after rain
- See if water appears in the same spots
- Feel for moisture along the walls
What to Do After the Water Recedes
Once the rain stops, dry the garage as quickly as you can. Remove standing water with a wet/dry vac or a mop. Open the door and windows to increase airflow. Use fans and a dehumidifier to dry the concrete and walls. The faster you dry, the less chance of mold growth. Wear gloves and boots if the water is dirty.
If the flooding is extensive or the garage has drywall or stored items, local water damage pros can handle the drying and cleaning. They can also check for hidden moisture in walls and floors. For ongoing issues, fix the root cause before the next storm. That might mean improving drainage, repairing the door seal, or installing a drainage system. Act quickly to prevent lasting damage.
- Remove standing water with a pump or wet/dry vac
- Use fans and a dehumidifier to dry the space
- Remove wet cardboard and paper items
- Clean and disinfect surfaces if water was dirty
- Monitor for mold growth over the next few days
Water damage does not wait
Water keeps spreading into floors and walls, so it is worth acting early. Calls are answered 24/7.
Call Now (480) 898-4279Frequently asked questions
Why does my garage flood only during heavy rain?
Heavy rain can overwhelm the drainage around your garage. If the ground is already saturated, water can't soak in, so it runs toward the lowest point, which is often the garage. A high water table or poor grading can make it worse. Check the slope and gutters first.
Can I fix the flooding myself?
Some fixes are simple, like cleaning gutters or replacing a door seal. Others, like regrading the yard or installing a drainage system, may need a professional. If you're unsure, a water damage inspection can tell you the cause and the right solution. Don't wait too long, as standing water can cause mold.
Will my insurance cover garage flooding?
Policies vary, and your insurer decides what is covered. Flood damage is often excluded from standard homeowners policies, but sewer backup or water seepage may be covered. Check your policy and talk to your insurance company about your specific situation. Document the damage with photos for any claim.