How to Repair a Leaking Garage Roof After Heavy Snow

Although heavy snow symbolizes winter holidays and seems innocuous, it can make garage interiors susceptible to leaks. Heat from garage attics causes higher portions of roofs to become warmer than areas along roof eaves, which makes snow on higher portions of garage roofs melt, and then freeze along the eaves. Frozen snow accumulated along the eaves becomes ice and snow dams that inhibit melted snow from draining off the roof, ultimately causing the water to back up and seep underneath the shingles. Since leaks may damage garage interiors, promptly repair a leaking garage roof caused by heavy snow and dams.

Box fan
Pantyhose
Calcium chloride ice melt pellets
Ladder
Long-handled aluminum roof rake with wheels
Disposable gloves
Water-based liquid roof coating sealer
Wooden paint stir stick
Paintbrush

Instructions

- 1
  Place a box fan in the garage attic to promptly stop the leak before you address the dam on the roof. Aim the fan toward the underside of the roof, directly at the leak. The cool air from the fan will freeze the water and prevent any more water from leaking into the garage.
- 2
  Fill an old pair of pantyhose with calcium chloride ice melt pellets. Tie off the opening of the pantyhose to prevent the pellets from falling out.
- 3
  Prop a ladder against the roof to allow you to access the dam. Lay the hose so it crosses over both the dam and the gutter. Calcium chloride pellets melt ice and snow quickly, creating a channel for trapped water to drain off the garage roof.
- 4
  Wait for a warm, sunny day when the snow begins melting to completely clear off the dam and fully eliminate any persisting leaks. Pull the accumulated snow off the eaves of the garage roof using a long-handled aluminum roof rake with wheels. Stand on the ground while you rake the snow off the roof.
- 5
  Check that the temperature is above 50 degrees Fahrenheit and the garage roof is fully dry before undergoing any repairs. Put on disposable gloves before using roof repair products.
- 6
  Open a container of water-based liquid roof coating sealer, and then stir it with a wooden paint stir stick. Apply the roof sealer evenly to the roof shingles using a paintbrush. Fully coat the regions of the garage roof that leak during heavy snow periods. Use a 4-gallon pail of roof coating per 400 square feet of roofing.
- 7
  Let the first coat of the roof sealer cure on the shingles for 24 hours.
- 8
  Apply another coat of the liquid roof coating sealer to the cured sealer using the previous techniques. Two coats is necessary to fully seal leaks and provide complete protection against the weather.
- 9
  Let the second coat cure for 24 hours.

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