Water intrusion under garage doors is a common problem that can lead to significant damage if not addressed promptly and effectively. Whether due to improper installation, insufficient sealing, or extreme weather conditions, water seepage can compromise the integrity of your garage and the items stored within it. In this comprehensive guide, we will explore various solutions to prevent water from getting under garage doors. This guide is structured to provide in-depth insights into understanding the problem, identifying its causes, and implementing effective solutions.

Understanding the Problem

Common Causes of Water Intrusion

Water getting under garage doors can be attributed to several factors. Understanding these causes is the first step in addressing the issue effectively.

Poor Garage Door Installation

Improper installation of the garage door can leave gaps between the door and the floor, allowing water to seep through. This issue can be exacerbated by uneven floors or misaligned door tracks.

Inadequate Sealing

Garage doors are equipped with seals and weatherstripping designed to keep water and debris out. Over time, these seals can wear out or become damaged, reducing their effectiveness.

Sloped Driveways

A driveway that slopes towards the garage can direct rainwater straight to the garage door. Without proper drainage, this water will eventually find its way inside.

Heavy Rain and Flooding

Extreme weather conditions, such as heavy rain or flooding, can overwhelm existing drainage systems and force water under the garage door.

Groundwater Seepage

In areas with high water tables, groundwater can rise and penetrate through the garage floor, especially if the floor is not properly sealed.

Risks Associated with Water Getting Under Garage Doors

Allowing water to seep into your garage can lead to several problems, including:

  • Structural Damage: Continuous water exposure can weaken the garage’s foundation and walls, leading to cracks and other structural issues.
  • Mold and Mildew: Moist environments are ideal for mold and mildew growth, which can pose health risks and damage stored items.
  • Damage to Stored Items: Water can ruin tools, equipment, and other items stored in the garage.
  • Increased Humidity: Excess moisture can raise the humidity level inside the garage, affecting vehicles and other metal items by causing rust and corrosion.

Initial Assessment

Before implementing any solutions, it is essential to assess the current state of your garage door and its surroundings. This assessment will help identify the specific issues causing water intrusion.

Inspecting the Garage Door and Surroundings

Start by examining the garage door itself. Look for visible gaps, worn-out seals, or misaligned tracks. Check the floor for signs of water damage, such as discoloration or warping.

Identifying Water Entry Points

Next, identify where the water is entering. This could be along the edges of the door, through the floor, or even from the walls. Use a flashlight to inspect hard-to-see areas and mark the spots where water intrusion is most evident.

Prevention Solutions

There are several preventive measures you can take to stop water from getting under your garage door. These solutions range from simple DIY fixes to more complex installations.

Garage Door Seals and Thresholds

Installing new seals and thresholds can create a barrier that prevents water from entering the garage.

Types of Garage Door Seals

  • Bottom Seals: These are attached to the bottom edge of the garage door and compress against the floor when the door is closed.
  • Weatherstripping: Applied along the sides and top of the door frame, weatherstripping helps seal gaps around the door.
  • Threshold Seals: These are installed on the garage floor, creating a raised barrier that the door closes against.

Installation Tips

  • Ensure the floor is clean and dry before installing any seals.
  • Measure the width of the garage door to cut the seals to the correct length.
  • Use adhesive and screws as recommended by the manufacturer to secure the seals in place.

Floor Drainage Systems

Proper drainage is crucial in preventing water buildup around the garage door. Installing a floor drainage system can help divert water away from the garage.

Types of Drainage Systems

  • Trench Drains: Installed across the garage entrance, these drains collect and channel water away from the door.
  • French Drains: These are installed along the perimeter of the garage and driveway, directing water away from the structure.
  • Slope Adjustment: Adjusting the slope of the garage floor or driveway can also help direct water away from the door.

Installation Tips

  • Choose a drainage system that suits your specific needs and local climate conditions.
  • Ensure proper installation to avoid clogging and maintenance issues.
  • Regularly clean and maintain the drainage system to ensure its effectiveness.

Proper Landscaping and Grading

The landscape around your garage plays a significant role in water management. Proper grading and landscaping can prevent water from pooling around the garage door.


Ensure that the ground slopes away from the garage to direct water runoff away from the structure. This can be achieved by adding soil around the foundation and ensuring proper compaction.


Incorporate features such as gravel beds, swales, and rain gardens to manage water flow. Avoid planting trees or shrubs too close to the garage, as their roots can interfere with drainage systems.

Waterproofing Products and Techniques

Waterproofing the garage floor and walls can provide an additional layer of protection against water intrusion.

Waterproof Coatings

Applying a waterproof coating to the garage floor and walls can help seal any cracks and prevent water from seeping through.


Installing waterproof membranes under the garage floor can provide long-term protection against groundwater seepage.


Use high-quality caulking to seal gaps and joints around the garage door, floor, and walls. This prevents water from entering through small openings.

Repair and Maintenance

Regular maintenance and timely repairs are crucial in keeping water out of your garage.

Fixing Damaged or Worn Seals

Inspect the seals regularly for signs of wear and tear. Replace damaged or worn-out seals promptly to maintain an effective barrier against water.

Garage Floor Repairs

Address any cracks or damage to the garage floor immediately. Use concrete repair products to fill cracks and prevent water from seeping through.

Regular Maintenance Tips

  • Clean the garage door and surrounding area regularly to prevent debris buildup.
  • Inspect and clean the drainage system periodically to ensure it is functioning correctly.
  • Check the seals and weatherstripping at least once a year and replace them as needed.

Advanced Solutions

For more severe water intrusion issues, advanced solutions may be required.

Installing a Sump Pump

A sump pump can help manage water that accumulates under the garage floor. It collects water in a sump basin and pumps it away from the garage.

Installation Tips

  • Choose a sump pump with sufficient capacity for your needs.
  • Ensure proper installation and maintenance to prevent pump failure.
  • Consider adding a battery backup to the sump pump to ensure it works during power outages.

Professional Waterproofing Services

For complex water intrusion problems, professional waterproofing services may be necessary. These services can provide a comprehensive solution, including advanced drainage systems, waterproofing membranes, and structural repairs.

Case Studies and Success Stories

Real-life examples can provide valuable insights into effective solutions for water getting under garage doors. This section will highlight several case studies and success stories from homeowners who have successfully addressed this issue.

Case Study 1: Garage Door Seal Replacement

Problem: A homeowner in Vancouver, BC, experienced water seepage under their garage door during heavy rains.

Solution: The homeowner replaced the old, worn-out bottom seal with a new, high-quality rubber seal. Additionally, they installed a threshold seal on the garage floor.

Outcome: The new seals effectively prevented water from entering the garage, even during severe weather conditions.

Case Study 2: Trench Drain Installation

Problem: A sloped driveway in Surrey, BC, directed water towards the garage, causing frequent water intrusion.

Solution: The homeowner installed a trench drain across the garage entrance to capture and divert water away from the door.

Outcome: The trench drain significantly reduced water buildup around the garage door, keeping the interior dry.

Case Study 3: Professional Waterproofing

Problem: A homeowner in Burnaby, BC, dealt with persistent groundwater seepage through the garage floor.

Solution: The homeowner hired a professional waterproofing service to install a waterproof membrane under the garage floor and apply a waterproof coating to the walls.

Outcome: The comprehensive waterproofing solution eliminated groundwater seepage, protecting the garage and its contents.

FAQs and Troubleshooting

Common Questions

  • How often should I replace garage door seals?
    • Garage door seals should be inspected annually and replaced every 1-2 years, or as needed based on wear and tear.
  • Can I install a drainage system myself?
    • While some drainage systems can be DIY projects, it is often best to hire a professional to ensure proper installation and functionality.
  • What is the best way to prevent water from getting under my garage door?
    • A combination of high-quality seals, proper drainage, and regular maintenance is the most effective way to prevent water intrusion.

Troubleshooting Tips

  • Water Still Entering After Sealing: Check for additional entry points or consider installing a drainage system.
  • Seals Not Effective: Ensure seals are installed correctly and consider upgrading to higher-quality materials.
  • Persistent Water Buildup: Evaluate the landscape and grading around the garage, and consider professional waterproofing services.