How to Fix a Leaking Window

March 14, 2024



 A closeup of a leaky window seeping onto the frame

Leaking windows can quickly become an overwhelming problem for any homeowner.

When a window begins to leak or condensation starts to build up, it can compromise your home’s comfort, pose risks of water damage, and even become a breeding ground for mould. That’s why it’s important to find out why a window is leaking and how to fix it before it causes greater damage.

In this article, we’ll guide you through temporarily fixing leaky windows and knowing when to replace them.

Understanding What Happened to Your Windows

Before beginning window leak repair, it’s important to understand how the leak might have occurred. This understanding will help you to prevent the issue in the future. Let’s look at several of the reasons that windows leak:

 A double-glazed window with a bit of snow covering its frame

Image source: Canva

Degraded Caulking or Sealant

The glazing putty holds the window in place. However, it can become brittle over time and cause the glass to rattle within the window frame, allowing cold air and water to seep in.

Poor Installation

Improperly installed windows can create gaps between the frame and the wall, allowing water to seep in. Faulty window flashing is another cause of window leaks.

Damaged Weatherstripping

Windows that are constantly exposed to harsh elements can have worn out weatherstripping, failing to create a tight seal.

Temporary Fix for Leaking Window

If you’re panicking trying to figure out how to fix a leaking window but aren’t sure where to start, take a deep breath! A temporary fix can provide immediate relief while you assess the situation.

Start by inspecting the window frame for visible gaps or damage. Once you find the problem area, you have a few options. 

1. Recaulk With Waterproof Caulk

Recaulking or resealing your leaky window is ideal for small cracks or gaps around the window frame. It provides a flexible and waterproof barrier against water intrusion. This solution is effective for addressing leaks where the window frame meets the wall or where glass panes meet the frame.

Follow the steps below to fix leaking windows with this method. Use an exterior-grade caulk for the outside and a regular silicone one for the inside.

  1. Begin by pulling off any loose or cracked caulking.
  2. Wash the area with a warm water and soap.
  3. Then put your tube of caulk in a caulking gun and cut the tip to a 45-degree angle with a knife to match the window frame.
  4. Use a nail to puncture the caulk tube. 
  5. Apply a continuous strip of caulk on the window and the frame. Avoid spaces and bubbles in the joints between the two. 
  6. Then run your fingers over the caulk to flatten the material out and ensure a smooth surface. 
  7. Repeat the process on the other sides of the window. If you plan on painting the caulk afterward, leave it to dry overnight to avoid damaging the newly caulked window space.
A person applying window caulking on a window sill

Image source: Canva

2. Reglaze Your Leaky Window

Reglazing windows can be ideal for leaks arising from cracked glazing putty. You'll need glazing putty to begin the reglazing process.

  1. Chip off the old window glazing with a small knife. During this process, make sure to keep the small triangular points in place, as they will hold the window steady as you work.
  2. Sand the window frame by hand and then wipe off the dust with a rag.
  3. Once the sanding has been completed, take a piece of glazing compound from the container and then roll it around in your hands until it’s completely pliable. 
  4. Then, form the compound into a cylindrical shape, lay it on the frame around the window, and push it into place.
  5. Then, flatten the glazing compound by holding the knife blade at a 45-degree angle from the edge of the frame. 
  6. Starting from one end, draw the knife along the putty. This should create a flat glazing surface that extends from the window to the frame. 
  7. You can then repeat this process on the other three sides of the frame.

Over the next 10 days, the putty should harden and seal any water leaks, making your windows perform like new!

3. Replace the Window

If your windows still leak even after recaulking and reglazing them, the problem may be poorly installed windows or that they’ve exceeded their lifespan.

This is when purchasing high-efficiency vinyl windows may be the right next step. Replacing the window is the most effective long-term solution for severe or recurring leaks.

Consult with a professional to assess the extent of damage and choose a replacement window that offers improved sealing and energy efficiency. Proper installation ensures a watertight seal and protects your home from future leaks!

Say Goodbye to Window Leaks With Clera Windows + Doors

Knowing how to fix a leaking window is a valuable life skill but oftentimes a window leak is a sign of bigger troubles, which cannot always be fixed with DIY solutions. 

If recaulking and reglazing your windows didn’t work, it might be time to consider high-efficiency vinyl window replacements manufactured by the experts at Clera Windows + Doors. 

As Ontario’s leading window and door manufacturer, we can help you choose the ideal window replacement for your home. From the design to installation, we handle it all so you don’t have to worry about window leaks damaging your home. You can also forget costly repairs and replacements with our lifetime warranty, giving you the best value for your money. 

Contact our expert team today for a free in-home estimate!

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