Will New Windows Keep My House Cooler in the Summer?
As the summer heat sets in, you might notice that your home feels like an oven, no matter how low you set the thermostat. If your air conditioning is constantly running but certain rooms are still uncomfortably warm, your windows are likely the culprit. According to the Department of Energy, heat gain through older, inefficient windows is responsible for up to 30 percent of a home’s cooling costs.
If you are wondering whether new windows will actually keep your house cooler, the short answer is yes. Modern replacement windows utilize advanced insulation technology to block heat from entering your home, drastically reducing the strain on your HVAC system.
Here is exactly how new windows help with heat reduction and temperature control year-round.
How New Windows Help with Heat Reduction
Old, single-pane windows or aging double-pane windows with broken seals do very little to stop the sun’s radiant heat. The glass heats up and transfers that warmth directly into your living space. Upgrading to modern, energy-efficient windows solves this problem in three distinct ways:
Double and Triple-Pane Insulation
Modern replacement windows feature two or three panes of glass separated by a microscopic gap. This gap is filled with an inert, non-toxic gas, typically argon or krypton. Because these gases are much denser than standard air, they act as an invisible barrier that drastically slows down heat transfer. The blazing summer heat stays trapped outside, allowing your interior to remain naturally cooler.
Low-E (Low-Emissivity) Glass Coatings
One of the biggest advancements in window technology is the Low-E coating. This is a microscopic, transparent metallic layer applied directly to the glass. During the summer, the Low-E coating acts like a mirror for infrared heat and ultraviolet (UV) rays, reflecting the sun’s thermal energy away from your home while still allowing visible light to shine through. This not only keeps the house cool but also protects your furniture, flooring, and artwork from fading.
Advanced Frame Materials
Heat does not just travel through the glass; it also travels through the window frames. Older aluminum frames conduct heat very easily. High-quality vinyl or fiberglass frames provide superior thermal resistance, ensuring the edges of your windows do not become hot spots during the summer.
How to Keep Windows Cool in Summer
If you are waiting to replace your windows or want to maximize the efficiency of your new ones, there are several steps you can take to block out the summer heat:
- Keep blinds and curtains closed: Closing your window treatments during the hottest parts of the day, particularly on south and west-facing windows, prevents direct sunlight from baking your rooms.
- Install blackout shades or thermal curtains: These heavy fabrics provide an extra layer of physical insulation against the glass.
- Apply a solar window film: If your windows are still in good condition but lack a Low-E coating, applying a heat-control window film can help reflect UV rays and reduce solar heat gain.
- Use exterior shading: Installing awnings or exterior shades physically blocks the sun before its rays ever touch the glass.
Why is Cold Air Coming Through New Windows?
While new windows are designed to keep the summer heat out, they are equally important for keeping the winter cold out. If you recently had replacement windows installed and you feel cold air coming through them, it is usually caused by one of three issues:
- Poor Installation: The most common reason for a drafty new window is improper sealing during installation. If the gaps between the window frame and the wall of your house were not properly insulated and caulked, outside air will seep in.
- Weatherstripping Issues: The weatherstripping that seals the moving parts of the window might be misaligned, damaged, or not fully engaged when the window is locked.
- Convection Currents: Sometimes, what feels like a draft is actually a convection current. If the air inside your home is warm and the window glass is very cold, the warm air hits the glass, cools rapidly, and drops to the floor, creating a feeling of moving air. High-efficiency double-pane windows usually prevent this, but it can still happen during extreme freezes.
Frequently Asked Questions About Windows and Home Temperature
Will new windows reduce my air conditioning bill?
Yes, upgrading to energy-efficient windows can significantly lower your cooling costs. By using Low-E glass coatings and insulating argon gas, modern replacement windows block radiant heat from the sun. This means your air conditioning unit does not have to work as hard or run as long to maintain a comfortable temperature inside your home.
Do new windows help with humidity?
Absolutely. Older windows often have broken seals or deteriorated weatherstripping that allows warm, humid outside air to seep into your home. New, properly installed windows create an airtight barrier that keeps excess moisture out, helping your home feel cooler and more comfortable during sticky summer months.
Why does my house get so hot even with the AC running?
If your air conditioning is running constantly but your house is still hot, your windows are likely the primary source of heat gain. Single-pane glass or uninsulated aluminum frames allow the sun’s thermal energy to transfer directly into your rooms, counteracting the cool air your HVAC system is pushing out.
Is it better to replace windows in the summer or winter?
You can replace windows year-round. While many homeowners choose to replace their windows in the spring or summer, doing it before the peak heat of summer arrives ensures you get the immediate benefits of a cooler home and lower energy bills during the hottest months of the year.
How can I tell if my old windows are losing energy?
The easiest way to check for energy loss is to stand near your windows on a very hot or very cold day. If the glass feels exceptionally hot to the touch in the summer or freezing in the winter, the insulation has failed. You can also light an incense stick or candle and hold it near the window frame; if the smoke wavers, you have an active air leak.
North Country Windows & Baths in Lincoln, NE, and the Surrounding Areas
At North Country Windows & Baths, our Windows are backed by a Lifetime Warranty giving our customers peace of mind. Each window is custom-made to fit your home with state-of-the-art engineering by design, and energy efficiency enhanced by style. Our windows are made to last for years of maintenance-free beauty.
Whether you want a soaker tub surrounded by subway tile or a low threshold shower with granite-like walls, you can customize your BathWraps space and even add accessories like soap dishes, caddies, seating, grab bars, and more Contact us today.
