Water is coming into my garage when it rains. Who do I call?
Usually, start with
Drainage professional
If water enters the garage during rain, a drainage professional commonly evaluates how water is moving around the garage and whether runoff, grading, drains, or other exterior conditions are contributing.
Change course if
The water is entering through a wall or wall-to-floor joint
A waterproofing or foundation professional may also be relevant when the entry point appears to be through the building enclosure.
The water is coming mainly under the closed garage door
A garage-door professional may be relevant if the opening, threshold, or bottom seal appears to be the main entry path.
A plumbing fixture, appliance, or pipe may be involved
A plumber may be relevant when the water is not tied to rainfall or appears to originate from plumbing.
Who handles what
Drainage
Evaluates exterior water movement, grading, runoff, drains, and conditions that direct water toward the garage.
Waterproofing / foundation
Evaluates water entering through below-grade walls, joints, or other parts of the building enclosure.
Garage door
Evaluates the door opening, threshold contact, and weather-sealing components.
What might be happening
Rainwater can reach a garage by more than one path. Surface runoff may move toward the opening, water may collect against the structure, or an opening or joint may provide an entry path. Seeing water inside does not by itself identify which path is responsible.
Useful things to notice
Where you first see the water
The door opening, a wall edge, a floor joint, or a localized wet area can help a professional trace the entry path.
What happens outside during rain
Pooling, flowing water, overflowing drains, and the direction water moves are useful observations.
Whether it happens only in certain storms
Wind direction, rainfall intensity, and duration can help distinguish intermittent entry conditions.
Before you call
Note when the water appears, where it first becomes visible, and whether it follows heavy rain, wind-driven rain, or prolonged wet weather. Photos or short video taken during the event are especially useful.
Before you fix the visible symptom
Sealing the first visible gap may not address the route the water is taking. When exterior water movement is involved, identifying the entry path and surrounding site conditions first can help avoid simply moving the problem elsewhere.
References
U.S. Environmental Protection Agency. Moisture Control: Precipitation Control.
U.S. Department of Energy, Building Science Education. Foundation Drain, Gutters, and Downspouts.
U.S. Environmental Protection Agency. Moisture Control Guidance for Building Design, Construction and Maintenance.