The short answer
Common Causes of Storefront Window Leaks
Storefront windows are large and exposed to wind-driven rain. The most common leak sources are deteriorated sealant around the glass, gaps in the metal frame joints, and missing or damaged flashing above the window. Over time, UV rays and temperature changes cause caulk to crack and pull away, leaving a clear path for water.
Another frequent culprit is the weep holes at the bottom of the frame. These small openings are meant to drain water that collects in the track. If they become clogged with dirt, paint, or debris, water backs up and spills over the sill into your building. A simple check of these holes can often reveal the problem.
How to Find the Leak Entry Point
Start by inspecting the exterior of the window on a dry day. Look for cracks in the caulk, missing sealant, or rusted metal. Pay close attention to the top corners and the joint where the window frame meets the wall. These are the most vulnerable spots for water intrusion.
Inside, look for water stains, peeling paint, or damp drywall near the window. If you can, have a helper spray water on the window from outside while you watch inside. This can help pinpoint the exact leak location. Remember that water may travel along framing before it appears, so the visible stain might not be directly below the leak.
- Check the sealant around all four sides of the glass
- Look for gaps in the metal frame corners
- Inspect the flashing above the window
- Clear any debris from the weep holes
- Examine the condition of the window gaskets
- Look for rust or corrosion on the frame
Dealing with Water Damage Inside
Once water enters, it can soak into drywall, wood framing, and insulation. That can lead to staining, warping, and even mold growth if left untreated. You should dry the affected area quickly and remove any soaked materials that cannot be saved. Use fans and dehumidifiers to speed up the drying process.
If the leak has been happening for a while, you might notice a musty odor or visible mold. Mold can be a health concern, so see a doctor if you feel unwell. For significant water damage, local water damage pros can assess the extent and help with drying and repairs. They have the equipment to detect hidden moisture in walls and floors.
- Remove wet curtains, blinds, and furniture
- Use a wet vacuum to extract standing water
- Set up fans to circulate air
- Run a dehumidifier to reduce humidity
- Cut away soaked drywall if needed
- Dispose of water-damaged carpet or padding
Temporary Fixes You Can Do Yourself
If you find a small crack in the caulk, you can apply a fresh bead of exterior-grade silicone sealant. Clean the area first and let it dry completely. This can stop a minor leak until a more permanent repair is done. For larger gaps or damaged flashing, you may need a professional.
You can also adjust the window itself if it is operable. Check that the window closes tightly and that the locks are engaged. Sometimes a simple adjustment of the hinges or latches can improve the seal. However, if the frame is warped or the glass is loose, those are signs of a bigger problem.
When to Call in the Pros
Some storefront window leaks are easy to fix, but others require special tools and knowledge. If you cannot find the source, or if the leak is large and causing repeated damage, it is time to get professional help. Local water damage pros can inspect the area, identify hidden moisture, and recommend the right next steps.
They can also help with the aftermath of water damage, including drying, cleaning, and repairing drywall or other materials. If the leak is related to the roof or the building structure, a roofer or a general contractor may be needed. Your insurance company may cover some of the costs, but policies vary, and your insurer decides what is covered. Check your policy to understand your coverage.
- You cannot locate the leak source
- Water damage is extensive or recurring
- You see mold growth or smell mildew
- The window frame is warped or rotting
- You need help drying out walls or floors
- The leak returns after a simple caulk repair
Talk to someone now
Water keeps spreading into floors and walls, so it is worth acting early. Calls are answered 24/7.
Call Now (386) 272-5697Frequently asked questions
Can a storefront window leak be fixed from the inside?
Temporary fixes like applying sealant from the inside can stop a small drip, but the real problem is usually on the exterior. You need to seal the outside to prevent water from getting behind the frame. Otherwise, moisture can remain trapped and cause more damage.
How do I know if my window leak is causing mold?
Look for black or green spots on walls, a musty smell, or worsening allergy symptoms. Mold can grow within 24 to 48 hours in damp conditions. If you suspect mold, see a doctor if you feel unwell and consider having a mold professional assess the area.
Will my insurance cover the water damage from a window leak?
Coverage depends on the cause of the leak and your specific policy. Some policies cover sudden accidental water damage, while gradual leaks may be excluded. Policies vary, and your insurer decides what is covered. Check your policy documents or contact your insurance company for details.