September 1, 2025
If you’re planning a window replacement in Rochester, Buffalo, or Syracuse, understanding U-factor and energy ratings can help you make smarter, more energy-efficient choices for your home. These key performance indicators reveal how well a window insulates, keeps your energy bills down, and improves year-round comfort in Upstate NY’s changing climate. At Wonder Windows, we offer a wide selection of high-performance products designed to meet your needs, and we’re here to help you choose the best fit.
What Is U-Factor and Why Does It Matter?
U-factor measures how well a window prevents heat from escaping. The lower the U-factor, the better the window insulates your home. In cold-weather regions like Western and Upstate NY, this is especially important for keeping warm air inside and reducing heating costs during long winters.
ENERGY STAR® recommends a U-factor of 0.30 or lower for our region. For example, the Wonder Star Double Hung Window (OKNA 800 Series) is a top-rated option that features Heatseal® spacers, multi-layer weather stripping, and triple-pane glass configurations with U-factors as low as 0.20.
Other Energy Ratings to Know
While U-factor is crucial, there are two additional metrics worth considering when selecting energy-efficient windows:
- Solar Heat Gain Coefficient (SHGC): Measures how much heat from sunlight passes through. A lower number helps block unwanted heat during the summer.
- Visible Transmittance (VT): Indicates how much daylight is let through. Higher numbers mean more natural light and less reliance on artificial lighting.
Windows like the Wonder Window Double Hung (Starmark EVO Series) provide excellent performance across all three ratings, combining superior insulation with strong light transmittance and low solar gain.
Explore Trusted Window Options from Wonder
Whether you're focused on insulation, visibility, or ventilation, we have a variety of window styles and materials to match your priorities. For example:
- Wonder Star Casement Windows offer sleek views and tight seals for high energy performance.
- Wonder Choice Sliding Windows are perfect for maximizing airflow with a space-saving design.
- Looking for value? Our Price Beater Double Hung Window gives you great performance at an unbeatable price point.
All of our windows are built for durability and low maintenance, featuring vinyl or composite frames, advanced weather stripping, and customizable finishes to match your home’s aesthetic.
Choose Energy-Efficient Windows with Confidence
When you understand U-factor and energy ratings, you're in a better position to choose windows that deliver long-term comfort and efficiency. Whether you're replacing one window or upgrading your entire home in Rochester, Buffalo, or Syracuse, Wonder Windows is here to help.
Contact us today to schedule your free consultation and explore the energy-saving window options that are right for you.
