Condensation on a window causing it to leak.

If your windows are old, leaks are relatively common. The cause of the leaks may be from various sources ranging from improper installation to a deteriorating seal. To remedy the problem, it’s essential to know the source of the leak. 

As you look for the source, you may notice telltale signs like moisture entering your home. You may have seen an increase in your utility bills, smelled mold or mildew growing in the wall, or observed water on your windowsill or flooring. 

Read on to gain valuable insight into why your windows may be leaking and what to do about it

Why Your Windows May Be Leaking 

1. Window damage

If your windows have lost their insulation properties and are cracked due to damage from a harsh storm (or stray baseball!), the situation should be resolved promptly to avoid damage from moisture intrusion. Additionally, you’ll want to remedy the damage swiftly to safeguard your home’s security. 

2. Incorrect installation techniques 

There are two main ingredients to obtaining high performance from your windows: superior manufacturing, and proper installation. If they aren’t installed correctly, they will leak and cause damage to your home. Specialty-shaped, bay and bow, and custom-made windows are more susceptible to leaking than other types. Keys to keeping leaks at bay and avoiding moisture intrusion are proper sealants or overhangs. 

When you need new windows, find a reputable replacement window contractor (like us!) with a track record of successful installations. Read online reviews, check with the Better Business Bureau (BBB) and Angi, and ask for referrals from your friends, family, and neighbors who had replacements recently. Get estimates from more than one contractor, decide which is the best fit for your needs, and you’ll invest in new windows confidently. 

3. Improper fit 

When windows don’t fit snugly in the space where they are installed, they will likely end up leaking and causing damage to your home. Hiring a contractor who pays attention to detail can prevent this problem in the future. 

4. Broken seals

If water enters your home around your window’s top, sides, or bottom, it may be because your caulking or sealant has cracked and is deteriorating. Broken seals can also show up as flattened or worn-out weather stripping. The result of either of these situations is heat loss and moisture penetration, which should be addressed promptly to minimize further damage. 

5. Aging glass

If condensation appears between your double- or triple-pane glass, the glass seal may be broken, causing air to leak. The argon or krypton gas that should be between your panes to provide insulation has leaked out due to the aging seal. While you can live with this situation, new windows will increase your home’s energy efficiency

At times when the glass seal wears out, water may get in through the broken seal, creating moisture damage to your windowsill. If left unaddressed, wood rot, mold, and deterioration will occur. 

6. Lack of waterproofing paint seal

Your window’s exterior molding that keeps it snugly fitted should be painted in a way that the paint slightly overlaps your windowpane. This is to ensure a waterproof seal is formed to keep moisture outside where it belongs. The continuous paint membrane is meant to give your home one more layer of protection against leaks. If this is missing, water may intrude. 

7. Condensation buildup

If you have condensation, locating where it is will give you an indication of how to remedy it. If condensation is building up inside your house, it’s not a sign of a window leak. It may mean there is too much humidity in your home or not enough insulation around your window. If you use a dehumidifier or run your air conditioning unit, you’ll reduce condensation buildup.

8. Poor house design

Your leak may not have originated in your frame or glass. It may be that your house lacks overhangs that drain water from flowing off your roof and away from your property. The fascia boards above your window may have been installed at an improper angle. They should face outward to lead water away from your window. 

Solutions for Window Leaks in Your Home

1. Repairing 

Knowing what caused your window to leak will help you identify what type of repair it needs. If you’re concerned you have moisture damage, take a screwdriver and probe your wood windowsill with it to check for soft or decayed wood. 

If you aren’t sure what is causing your windows to leak, and you know they need to be repaired, contact a reputable contractor to assess the cause and make the necessary fixes

2. Resealing 

If your window is leaking due to deteriorating caulking or a broken seal, peel the old caulking off and replace it with new caulk. This will fortify your home’s protection from water infiltration and insulate it from outdoor temperatures. 

3. Replacing 

If your windows are old and leaking, the best long-term solution is to replace them. Replacements seal your home from leaks, insulate your house, lower utility bills, and ensure your home’s temperature is consistent throughout. Perfectly measured custom units ensure you won’t incur moisture infiltration in your home due to faulty windows. 

Fortify Your Home from Moisture Intrusion with Beautiful Replacement Windows 

Now that you have a better idea of the cause of your leaks, take a moment and learn more about how our window services can solve your moisture intrusion issues once and for all with gorgeous window replacements. 

Kelly Window & Door has provided over 4,000 successful installations in the greater Raleigh area using reputable products, and we’re here to serve you. We offer affordable vinyl and genuine wood windows to add beauty, charm, and protection from the elements to your home. 

Take the first step by visiting our showroom or scheduling a consultation at your home.