How To Fix a Leaking Skylight

How to Fix a Leaking Skylight During Winter

“How to Fix a Leaky Skylight During Winter” was written by a member of the Flex Seal Editorial Team.

A leaky skylight can be a homeowner’s worst nightmare, causing damage to your roof, ceiling, walls, and floors. Skylights are especially vulnerable to leaks in the winter, when snow and ice can accumulate, creating pressure on the frame and exposing weaknesses in the seal. Whether you’re facing a sudden leak or dealing with an ongoing issue, the Flex Seal Family of Products is here to help you effectively repair your skylight, even in challenging winter conditions.

In this blog, we’ll show you how to find where the leak is coming from and how to seal and protect your skylight using Flex Seal products.

Important Safety Information: Roof work is always dangerous, but the risk of falling is greatly increased during cold weather. A small patch of snow or ice can cause even the most careful homeowners to fall from their roofs. Do NOT attempt to climb onto your roof unless you are certain the roof is clear of snow and ice and use a proper harness and safety rope whenever you are working on elevated areas. Seek the help of a professional if you do not feel comfortable.

How To Identify the Source of Your Skylight Leak

Start by inspecting the following:

Flashing: The flashing is the metal (or plastic) installed around a skylight to direct the flow of water away from the roof and prevent leaks. Ensure there is a clear channel around both sides of the skylight and that the exposed flashing at the bottom of the skylight is clear of debris. Sometimes, simply removing debris from the upper side of the skylight will allow water to drain freely around it.

Be sure that the roofing on the upper edge and sides of the skylight is sealed to the flashing to prevent water from getting under it, and ensure that the flashing on the lower edge of the skylight lays flat on the roof.

Flexpert Tip: If your skylight flashing needs significant repair or replacement, it may be best to call a professional, as the repair could be beyond the scope of a DIY fix.

Roof: Snow buildup or ice dams can block water from properly draining off the roof, causing it to pool around your skylight and find its way inside. Inspect the shingles or flashing for any cracks or gaps that might allow water to seep in.

Skylight: Examine the glass or plastic assembly for any cracks or chips. Also, look at the seals around the skylight frame. If they are worn or cracked, water can easily get in.

Once you’ve identified the potential sources of the leak, it’s time to stop water from causing further damage by applying Flex Seal products.

How To Stop a Skylight Leak with Flex Seal Products

When your skylight is leaking, it’s important to act fast, especially if a winter storm is approaching. Here are some immediate solutions to seal your skylight.

1. Apply Flex Caulk

If you’ve found small cracks or gaps in the skylight, its gaskets, or around the frame, Flex Caulk is a quick and easy way to seal them. Its weather-resistant properties make it ideal for use during winter. Apply a bead of Flex Caulk around the edges of the skylight where the skylight meets the curb assembly and along any other desired areas, to prevent water from seeping in.

Flexpert Tip: Flex Paste in a caulking gun can also be used to seal these areas.

2. Use Flex Tape® for Emergency Patches

If your skylight or the surrounding flashing is severely damaged, Flex Tape® is a super-strong, waterproof tape that can temporarily patch cracks or holes. It works even in wet conditions, making it ideal for immediate repairs during a winter storm. These quick fixes can prevent further water damage and buy you some time until a more permanent solution is found.

Flexpert Tip: Flex Tape is meant to be a temporary solution for a leaking skylight. As soon as you’re able, it is important to address the root cause of the leak. Depending on the level of damage, you may need to call a professional to repair or replace the skylight or flashing.

Dealing with Snow and Ice Around Your Skylight

Winter weather doesn’t just cause leaks—it can make existing ones worse. Snow and ice buildup around your skylight creates pressure that can force water into even the smallest gaps, leading to leaks.

Here’s how to minimize the impact of snow and ice on your skylight:

Clear Snow Regularly: If you notice snow accumulating on your roof, use a roof rake to safely remove the buildup around your skylight. This reduces the weight and pressure on your roof, preventing ice dams from forming and worsening leaks. However, only do this if it’s safe—never climb onto a slippery roof during a storm.
Protect the Skylight with Flex Seal Liquid® When an existing roof is failing, applying Flex Seal Liquid® in the weathered area will create a watertight barrier that expands and contracts with the temperature, preventing cracks from forming as the weather changes. Depending on the type and condition of the roof, this emergency repair can minimize or stop water intrusion until permanent repairs can be made.

By keeping snow and ice at bay, you can prevent water from pooling around your skylight and reduce the risk of leaks during the winter months.

Long-Term Solutions to Prevent Future Skylight Leaks

While quick fixes and snow management are necessary in an emergency, it’s crucial to think about long-term solutions to prevent skylight leaks from recurring. Addressing the root causes of your leak will save you time, money, and stress in the future.

Here’s how you can prevent future leaks:

Repair or Replace the Flashing: The flashing is your skylight’s first defense against water, and when it’s compromised, leaks are inevitable. If the flashing around your skylight is cracked or damaged, it needs to be repaired or replaced.
Consider Skylight Replacement: If your skylight is older or has sustained significant damage, it may be time to replace it. Modern skylights are much more energy-efficient and weather-resistant, reducing the risk of future leaks. A new skylight, combined with proper flashing and installation, will give you peace of mind for years to come.
Inspect and Maintain Regularly: Inspect your skylight and the surrounding roof area at least once a year, especially before winter sets in. Look for any signs of wear and tear and address them before they become bigger problems.

A leaky skylight doesn’t have to spell disaster for your home. By identifying leaks and using Flex Seal products to repair them, you can help safeguard your home from costly water damage this winter and beyond.