When you have multi-pane windows for your home, you may have selected them because they offer extra protection against exterior temperatures, moisture, and drafts. Because the windows' glass panes have no visible cracking, you may believe that they are still fully intact and doing their job.

However, there may be damages that you cannot see that are affecting their effectiveness and stability, putting your home at risk for drafts, exposure to water, and decreased energy efficiency. Below are a couple of subtle signs to look for when trying to determine whether it is time to replace the glass in your home's multi-pane windows.

1. Condensation or Drops of Water Form on the Interior Surfaces of the Window Glass Between the Panes

One sign to look for that indicates it may be time to replace the glass panes in your home's multi-pane windows is the presence of condensation or drops of water. This excessive moisture will typically be found on the interior surfaces of the glass between the panes instead of on the outside.

If you are noticing this buildup of condensation or water, the seals around the glass have most likely started to deteriorate, causing it to become trapped between the panes. Especially if the windows are older, you should consider replacing the glass to keep mold from starting to grow on the frames or prevent deterioration of the frames from the water.

2. Glass Has Become Weak and Brittle and Is Starting to Show Small Stress Fractures on the Surfaces

Another subtle sign that you should look for when trying to ascertain the condition of the glass is small stress fractures on the surfaces of the frames. You may need to look at the glass at an angle while the sun is shining through or use a magnifying glass to see the fractures.

As glass becomes older and is subjected to rapid temperature changes and sunlight, it can become weak and brittle, causing small stress fractures to form. If the glass is not replaced, there is an increased risk that it will crack under the slightest pressure, even when you open and close the windows.

Even if a window's glass is not overtly broken, the seals around it may have deteriorated, as evidenced by condensation and water droplets on its surface between the window panes. The glass may also have become weak and brittle, which causes stress fractures on the surface. If you believe that your windows' glass has subtle signs of damage, contact a residential window glass replacement service in your area to speak with someone about your options.