How do I know if my windows need replacing?

Many first time home owners can easily become overwhelmed when trying to understanding what it really means to own and maintain their new homes. When it comes to windows, there have been a lot of changes in technology over the past 70 years. If your first home is older, looking at replacing windows is one of the smartest home improvements you can make. However, knowing when a window needs to be replaced may not be as transparent as it may first appear.

Unless you own an historic home, most residential houses have some kind of double or triple pane window. Because glass is a very poor insulator,  window manufacturers seal Argon gas between these panes. It's invisible, leaves the window completely transparent, and significantly reduces thermal transfer —  keeping mother nature outside and the heated or cooled air we've paid for inside where it belongs.

The problem comes when a window's seal fails, allowing the insulative Argon gas to escape, and the only thing between you and the elements are a couple panes of glass. For the most part, it's usually pretty easy to access if your windows have lost that important layer of insulation. On cold winter days, you might feel a cool breeze when you walk past your window. If you hold your hand an inch or two from the glass, you may feel cold (or heat in the summer) radiating from the window. This is a clear sign that your windows have broken seals and need replacing. 

Another telltale sign is if you see moisture or condensation (fogging) in between the panes of glass. When window seals break, the Argon gas escapes. This creates a vacuum, which then sucks in the ambient air. Air contains moisture, and that's what forms on the inside panels of your windows. When you see this, you know it's time to replace the window.

Other clues your windows need replacing is if you see mold or mildew forming on the glass, between the panes or on the window frame. This happens to windows with broken seals, especially in the winter or spring. Cold air hits one side of the window, which meets the warm air in your home on the other side of the glass. Moisture accumulates on it, making it an excellent breeding ground for mold and mildew. A window with the Argon gas intact would prevent this by blocking the thermal transfer.

It's always best to have a reputable window expert do an in-home consultation. But before you do, make sure to do a little homework and ask these questions:

  1. How long has the company been in business? Any warranties are only as good as the company who gives them. If the company goes out of business, your warranty goes too. Make sure your window company has an established history that is decades, not years old.

  2. Ask specifically what is covered in the warranty and it it's transferrable to the next home owner if you decide to sell. Does it only cover the product? Or does it include the cost of labor as well? Many companies only offer the manufacturer's product warranty, but then charge hundreds for the labor. Double check to ensure the warranty covers both.

  3. Do they use their own factory-trained employees for installations? Many companies hire temps or contractors who have not been properly trained to do installations. This is a huge red flag for quality issues down the road.

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