The Hidden Cost of Drafty Windows: How Air Leaks Drain Your Energy Bills

October 28, 2025

You may not see it, but those tiny drafts sneaking through your old windows could be costing you hundreds of dollars a year. Many St. Louis homeowners underestimate how much air leakage affects comfort and energy efficiency. The truth is, drafty windows don’t just make your home chilly in the winter and stuffy in the summer — they make your HVAC system work harder, driving your utility bills up month after month.


Here’s how to spot the signs of drafty windows, understand their real costs, and fix the problem for good.

1. Why Air Leaks Matter More Than You Think

Even a small draft can lead to big losses. When warm indoor air escapes during winter (or cool air leaks out in summer), your heating and cooling system has to replace that lost energy — often continuously.


According to the U.S. Department of Energy, air leaks can account for 25% to 40% of total energy loss in the average home. If your windows are older or poorly sealed, they could be a major reason your energy bills keep climbing.

2. How to Tell if Your Windows Are Drafty

Not sure whether your windows are leaking air? Here are a few easy ways to check:


  • The candle or incense test: Hold a lit candle or incense stick near the edges of your closed window. If the flame flickers or the smoke moves, air is leaking.
  • Visible light or gaps: Look for daylight peeking through around the frame or sash.
  • Condensation buildup: Persistent moisture or fog between panes can signal seal failure.
  • Temperature difference: If you feel cold or heat radiating near your windows, insulation is likely compromised.


If any of these sound familiar, it’s time to take action.

3. The Real Cost of Doing Nothing

While a few drafts may seem minor, they can quickly add up. Here’s what happens if you ignore them:


  • Higher energy bills: Your furnace or air conditioner runs longer to maintain the same temperature.
  • Uneven comfort: Some rooms stay cold while others overheat, creating hot and cold spots throughout your home.
  • Increased wear on HVAC systems: Overworking your equipment shortens its lifespan and can lead to expensive repairs.
  • Moisture damage: Persistent leaks can allow condensation, mold, or even wood rot to form around window frames.


Over a single heating or cooling season, those “small leaks” can waste hundreds of dollars in lost energy.

4. Temporary Fixes vs. Long-Term Solutions

If you’re not ready for a full replacement, you can try these short-term fixes:


  • Apply weatherstripping or caulk to seal visible gaps.
  • Use thermal curtains to reduce heat transfer.
  • Install plastic insulation film kits over drafty windows in winter.


However, these solutions are temporary. For lasting comfort and lower bills, replacing old or inefficient windows with energy-efficient models is the best long-term investment.


Modern windows with Low-E glass, insulated frames, and advanced sealing can drastically cut heat loss and improve overall comfort.

5. Why RRSA St. Louis Is the Smart Choice

At RRSA St. Louis, we specialize in energy-efficient window replacement that keeps your home comfortable all year long. Our certified installers use high-performance materials built for Missouri’s climate — so you’ll save energy, reduce drafts, and enjoy a quieter, cozier home.


We offer free inspections to identify air leaks and help you choose the right replacement windows for your home and budget.


Schedule your free window evaluation today.

Vinyl vs Fiberglass vs Wood Windows: Which Material Makes Sense for Missouri Weather?

October 28, 2025
When it’s time to replace your windows, one of the biggest decisions you’ll face is what material to choose for your window frames. Each type - vinyl, fiberglass, and wood - offers its own mix of looks, performance, and price.  For St. Louis homeowners, where summers are humid and winters can be bitterly cold, the right window material makes all the difference in comfort and energy efficiency. Here’s how to decide which is best for your home.

How to Know It's Time to Replace Your Windows - A Pre-Winter Checklist for St. Louis Homes

October 28, 2025
As temperatures drop and the Midwest winter approaches, St. Louis homeowners start preparing for the cold. But while you’re checking your furnace and sealing up doors, don’t overlook one of the biggest sources of heat loss in your home: your windows.  Old or inefficient windows can make your heating system work overtime, drive up energy bills, and leave your home feeling drafty. Before winter hits, use this checklist to find out if it’s time to replace your windows.

How New Entry & Patio Doors Boost Curb Appeal and Energy Efficiency

October 28, 2025
Your front door is one of the first things people notice about your home. It sets the tone for your curb appeal, influences your home’s value, and plays a big role in keeping your home comfortable and efficient.  If your entry or patio doors are old, drafty, or outdated, upgrading them can make a dramatic difference in both appearance and performance. Here’s how new doors can enhance your St. Louis home inside and out.

Is It Time to Replace Your Windows? 6 Warning Signs to Check Before Winter

September 29, 2025
As summer fades, St. Louis homeowners start thinking about cooler weather—and higher heating bills. Old or failing windows can let in drafts, drive up energy costs, and make your home less comfortable. Here are six signs it’s time to consider replacement windows before winter arrives.

Decoding Window Ratings: How U-Factor, SHGC, and Visible Transmittance Affect Your Home

September 24, 2025
Understanding Window Ratings: U-Factor, SHGC, and Visible Transmittance Explained

3 Ways To Prep Your Roof For Fall

September 29, 2022
We hope your end-of-summer BBQ was legendary. We hope you enjoyed your pool parties and porch-sitting. But time marches on and autumn is here. Before the cold weather hits, there’s a few things we think you should know about your roof – and steps you can take to make sure it stays functional and damage-free through the harsh winter months. As you might know, it costs an average of $7,200 to replace a roof in Missouri. Unfortunately, homes don’t really come with how-to manuals to protect roofs and avoid repairs, but RRSA has you covered. Let’s take a look at three ways you can prep your roof for fall and winter.

Three Signs Your Roof Is Getting Old

May 24, 2022
It’s hard to gauge the life expectancy of a roof. The best estimates put the lifespan of the average roof at between 20 and 30 years for standard asphalt shingles. Other materials, like clay and concrete, can last up to 100 years . Aside from materials, lots of factors play a role in aging or preserving a roof: temperature, exposure to elements (like wind and hail), and maintenance history. But no matter what kind of roof you have, it pays to know what the early signs of age and degradation are so that when you see them, you can act before your roof becomes compromised and begins to leak, which can cause thousands of dollars of damage , or otherwise fail. Let’s take a look at three warning signs that your roof is getting up there (pun intended).

Three Reasons A GAF Certification is Important

April 28, 2022
Did you know that only 2% of roofers in the U.S. qualify to be recognized as GAF Master Elite™ Contractors? That figure may seem small, but taken together with the fact that the roofing industry has a failure rate more than 50% — and much of that failure attributed to lack of knowledge — it starts to make a little more sense. If you’ve owned a home for more than a few years, you’ve likely heard stories (or had your own experiences) with bad roofers. When trying to avoid the shoddy workmanship, subpar product, and un-warrantied work, three letters are going to change the way you think about roofs and roofers: GAF. Let’s look at three reasons this particular certification ensures you get the most for your money.

Three Reasons To Consider Roof Ventilation

December 1, 2021
How often do you think about your roof? If you’re like most people, the answer is probably not a lot — after all, we’ve got plenty to think about without worrying about the condition of our houses. But a roof is one of those things that you really don’t want to fail on you when you need it most. On top of being a fairly expensive thing to fix, it’s also incredibly stressful to deal with when inclement weather is approaching. To this end, one of the best things you can do for the long-term health of your roof (and of your savings account) is to be proactive and consider roof ventilation. Let’s take a look at three reasons it’s a smart investment.