Is It Worth Replacing 20-Year-Old Windows?

Oct 26, 2025

Windows are one of the most important yet often overlooked features in a home. They shape the comfort, efficiency, and curb appeal of your property. But if your windows are about 20 years old, you might be wondering whether replacing them is really worth it. The short answer: yes, in most cases, it is.

Modern window technology has come a long way in the past two decades, offering superior insulation, noise reduction, and visual appeal. This detailed guide explores why replacing your 20-year-old windows is a smart investment, how to tell when it’s time, and what benefits you can expect when you upgrade.

How Long Do Windows Really Last?

Most residential windows last between 15 to 25 years, depending on the material, maintenance, and exposure to weather. Around the 20-year mark, windows often start to show signs of aging, such as drafts, condensation, or difficulty opening and closing.

In Northbrook, IL, where weather conditions range from humid summers to icy winters, the lifespan of a window can be shortened by temperature fluctuations and moisture exposure. This makes window replacement not only a matter of aesthetics but also comfort and energy efficiency.

Signs Your 20-Year-Old Windows Need Replacement

If your home’s windows are approaching or past their 20th birthday, look for the following signs that it’s time for an upgrade:

Drafts and Uneven Temperatures

Feeling cold air near the glass or around the frames indicates air leakage. Drafty windows force your heating and cooling systems to work harder, leading to higher energy bills.

Fogging or Condensation Between Panes

This is a telltale sign of seal failure. Once the insulating gas leaks out, the window loses its energy efficiency, allowing outdoor temperatures to affect indoor comfort.

Difficulty Opening or Closing

Windows that stick or jam often have warped frames, which can result from years of exposure to heat and moisture.

Visible Damage or Decay

Rotting wood, cracked glass, or peeling finishes suggest the window is past its prime and may no longer protect your home properly.

Outdated Design or Poor Curb Appeal

Old windows can make even a well-maintained home look dated. Modern replacements instantly refresh your home’s exterior and boost resale value.

Benefits of Replacing Old Windows

Replacing 20-year-old windows isn’t just about appearance; it’s about enhancing your home’s performance. Here are the key advantages of upgrading:

Improved Energy Efficiency

New windows with double or triple-pane glass, low-emissivity coatings, and argon gas fills significantly reduce heat transfer. This keeps your home cooler in summer and warmer in winter, reducing utility bills.

Enhanced Home Comfort

With better insulation and soundproofing, replacement windows maintain a more stable indoor temperature and reduce outdoor noise, ideal for busy suburban areas near Deerfield or Glenview.

Increased Home Value

Real estate experts note that window replacement projects have one of the highest returns on investment among home improvements. Homebuyers appreciate energy efficiency and a modern look.

Easier Maintenance

New vinyl or fiberglass windows require minimal upkeep, with no sanding, painting, or sealing needed, saving you time and effort.

UV Protection for Interiors

Modern windows block harmful UV rays, preventing your furniture, flooring, and drapes from fading over time.

Chart: Comparing Old vs. New Windows

Feature 20-Year-Old Windows Modern Replacement Windows
Energy Efficiency Low, often single-pane High, with double/triple panes
Insulation Poor seal, air leaks are common Tight seal, superior insulation
Maintenance Needs Frequent upkeep required Minimal maintenance
Noise Reduction Limited Significant
Aesthetic Appeal Outdated Modern, customizable designs
UV Protection Minimal Strong UV-blocking technology
Longevity Near the end of life 25–40 years or more

How Window Replacement Impacts Energy Bills

In older homes, inefficient windows can account for up to 25–30% of heating and cooling energy loss. By replacing your 20-year-old windows, you can lower your monthly energy expenses while improving indoor comfort.

Homes in Northbrook, IL, and nearby communities like Highland Park and Glenview especially benefit because of the area’s temperature extremes. The improved insulation from modern windows reduces drafts and helps HVAC systems operate more efficiently throughout the year.

Common Misconceptions About Window Replacement

“My Windows Still Look Fine, Why Replace Them?”

Even if your windows appear intact, hidden issues like failing seals or poor insulation can be draining energy and increasing costs without you realizing it.

“Window Replacement Is Too Expensive.”

While there’s an upfront investment, the long-term savings from reduced energy bills and increased home value make it worthwhile. Plus, modern windows require less maintenance, saving you more over time.

“I’ll Just Replace One or Two Windows.”

Replacing only a few windows can create uneven insulation and inconsistent aesthetics. A whole-home replacement ensures balanced comfort and curb appeal.

What to Consider When Choosing Replacement Windows

Frame Material

  • Vinyl: Low maintenance and energy-efficient

  • Wood: Classic look but requires upkeep

  • Fiberglass: Strong, durable, and energy-saving

  • Aluminum: Best for modern designs, but less insulating

Glass Options

Choose double-pane or triple-pane glass for better insulation and Low-E coatings for UV protection.

Professional Installation

Even the best windows won’t perform well if installed incorrectly. That’s why professional installation by experienced experts is crucial for long-term performance.

How Long Will New Windows Last?

With today’s materials and technology, modern windows can last 25–40 years or longer with proper care. That means replacing your old windows now could mean decades of improved comfort, beauty, and efficiency before another upgrade is needed.

Regular maintenance, such as cleaning tracks and checking seals, can further extend the lifespan of your new investment.

Transform Your Home with a Simple Conversation

When you’re ready to experience the comfort and efficiency of new windows, reach out to the trusted professionals at McCann Window & Exteriors Inc. located at 3375 Commercial Ave., Northbrook, IL 60062. They’ve been helping homeowners upgrade their homes with precision and care.

Whether you’re in Northbrook or nearby areas like Deerfield or Highland Park, their friendly team is ready to guide you through your window replacement options. Call 847-562-1212 today to schedule a consultation and discover how easy it can be to enhance your home’s comfort, beauty, and efficiency.

 

SEE WHAT OUR CUSTOMERS HAVE TO SAY
 I am very happy with the new windows McCann installed for us. They were able to install them quickly and did a very thorough job. Mark and Angel did a great job! I would highly recommend McCann to anyone looking to replace their windows. Thank you McCann! 
 I can only say good things about the people I dealt with with McCann, from Kevin, and Jim, and all the installers. They did a great job, their customer service was excellent, they were very clean, and I am as happy as can be. They were professional, and a pleasure to do business with. 
 Just nice people all around. They know their stuff, have several quality options to choose from (less to more expensive), & didn’t pressure sell. Easy install, quality workmanship. Super satisfied with our experience. 
Top 500 Qualified Remodeler in 2023
Nextdoor neighborhood faves in 2023
Guildmaster award for service excellence
Energy Star logo
Pella certified contractor
James Hardie logo
The image shows the word
Andersen Windows & Doors logo
A silver and blue badge reads
Pella Platinum Elite Certified Contractor badge featuring silver and black design with
Better Business Beureau A plus accredited business
McCann Window & Exteriors logo with two people, a window, and a house icon in white above orange text on a light background.

McCann Window & Exteriors

3375 Commercial Ave.
Northbrook, IL 60062
Get Directions

847-562-1212