Energy-efficient windows are made using quality materials and technology to help make your home more comfortable, lower heating and cooling costs, and lessen your impact on the environment. Depending on the climate that you live in, there are specific enhancements that can be made to the windows to improve energy efficiency. Options like multiple panes of glass, insulating gases, low-emissivity coatings, special spacers and seals can all contribute to increasing energy efficiency in your home's windows.
The US Environmental Protection Agency developed a program called ENERGY STAR® to provide credible, unbiased information that consumers can use to make educated decisions around products that save energy and help reduce the carbon footprint on the environment. Energy-efficient windows can help make your home more comfortable and may reduce your utility bills. Plus, you’ll have the added knowledge that you’re helping the planet by minimizing environmental impact.
Discover everything you need to know about energy efficiency, ENERGY STAR ratings and the different options available for glass and glazing. Stanek Windows offers a variety of vinyl window and patio door options that help you achieve long-term performance and energy cost savings, in any climate.
Energy efficiency is simply using less energy to do the same job. There are many ways to make your home more energy-efficient, but experts estimate that 70 percent of energy loss occurs in windows and doors. The more energy-efficient your windows and doors are, the more you’ll save on your energy bills and the more comfortable you’ll be in your home year-round.
ANSWER: U-Factor, also known as U-Value, is the measurement of the rate of heat transfer through a window. What U-Factor tells you is how well the window insulates. Values for U-Factor generally range from 0.15 to 1.25. A lower U-Factor number means the window is better at insulating and keeping heat in. The lower the number, the better the window will perform in reducing the amount of heat transfer. The less heat that transfers through a window, the more energy-efficient it is.
ANSWER: The Solar Heat Gain Coefficient (SHGC) measures the amount of solar radiation, or heat, that enters your home through a window or door. The number of glass panes and the type of glass coatings, like Low-E, can impact the amount of heat gain through a window. The values for solar heat gain coefficient range from 0 to 1. Like the U-Factor, a lower SHGC number is better, especially for warm climates like Arizona.
ANSWER: Energy efficiency doesn’t stop with upgrading your windows and doors. You can make your home more energy efficient by upgrading anything that requires energy to operate. Advances in energy-saving technology allow products such as appliances, furnaces, air conditioners, water heaters, electronics, lighting, building products, food service equipment and more to operate using less energy – making your home more energy-efficient.
ENERGY STAR requirements vary by product, and for windows, the requirements vary by climate zone. Zones in the US are broken into four areas; Northern, North-Central, South-Central and Southern. Within each zone, there are specific U-Factor and SHGC ratings that must be met for the window to qualify for the ENERGY STAR label. View ENERGY STAR’s performance chart.
ANSWER: ENERGY STAR doesn't have a set schedule for releasing changes to the guidelines, but as advancements are made and technology evolves, ENERGY STAR makes updates.
ANSWER: Having an ENERGY STAR certified window means that for the climate in which the window is installed, it has met the criteria set forth to earn the certification label. The certification label is your assurance that the window meets the guidelines for energy efficiency.
The type of glass and components in a window affects the flow of heat that passes through it, which plays a major role in how energy-efficient your home is. The best energy-efficient windows have multiple panes of glass and utilize special coatings, spacers and insulating gases to insulate better and reduce heat transfer.
ANSWER: To truly understand Low-E, it helps to have a general understanding of the light spectrum. Infrared light, ultraviolet (UV) light and visible light have different wavelengths and make up different parts of the solar spectrum. Visible light is what you want to maximize as it brings natural light into your home, but UV and infrared light are what you want to minimize. Low-E is a special microscopically thin coating that is applied to a window to do just that, reflect UV and infrared light away from your home. Low-E also reflects heat inside your home in the winter back into your house vs. out through the glass, helping to keep your home more comfortable..
ANSWER: UV light has damaging effects on the skin and causes furniture to fade. Infrared light is the type of light you can feel and is what causes you to feel hot after being in the sun. In a window, you want to allow visible light to pass through, but you want UV and infrared light to be reflected. Low-E coatings do just that. They reflect a substantial amount of UV and infrared light, reducing the transfer of heat, but allowing visible light to pass through into your home.
ANSWER: The simple physical difference between these windows is 1, 2 or 3 panes of glass. By nature, glass is a poor insulator, but it is abundant, easy to work with, transparent and allows light to pass through which is why it's used as a building material.
Single-pane windows keep the rain and snow out but do a poor job of keeping the temperature consistent in your home. In the winter, the heat from your furnace transfers easily through the glass right outside your home and in the summer, the heat from the sun transfers through the glass to the inside of your home.
Double-pane windows have a second layer of protection and insulation, but to get better performance from double-pane glass windows, additional components are needed like a Low-E coating, spacers, quality seals and insulating gas, typically argon, between the panes. It’s these add-ons that help make windows more energy efficient.
Triple-pane windows offer a third layer of protection and insulation, and like double-pane windows, the same add-ons are utilized for even better performance and energy-efficiency.
ANSWER:To the layperson, it is hard to understand exactly how adding things like Low-E coatings, spacers, seals, insulating gases and multiple panes of glass to windows reduce the transfer of heat to make your home more comfortable. So we like to use the following analogy. Imagine yourself standing at the bottom of an empty swimming pool. Your body represents heat. Now try running from one end of the empty pool to the other. It’s easy because there isn’t anything slowing you down. This is how single pane glass windows perform. They allow heat to transfer easily meaning in the winter when your furnace is pumping, that heat goes right out the window. And in the summer when the sun is at it's peak, all that solar heat is pumping inside your home.
Now imagine yourself in the same pool, this time with some water, let’s say up to your knees. Now try running from one end of the pool to the other. It’s not as easy as it was when the pool was empty. This is how double-pane glass windows perform. However, when you add on components to your double-pane windows like low-e coatings, spacers, seals, and insulating gas, as each component is added, imagine the water getting higher. Running from one end of the pool to the other becomes much more difficult the deeper the water gets. The water limits you from moving easily just as all the components added to the double-pane windows limit the transfer of heat. So in the winter when your furnace is pumping, the heat has a much more difficult time escaping through your windows. Conversely, in the summer, when the sun is baking your home, the solar heat has a much more difficult time entering your home through your windows.
Finally, imagine yourself in the same pool, this time with molasses, up to your knees. Try running from one end of the pool to the other. It’s much harder. This is how triple pane windows perform. When you add on components like low-e coatings, spacers, seals, and insulating gas, as each component is added, imagine the molasses getting higher. Running from one end of the pool to the other becomes nearly impossible. The molasses limits you from moving easily just as all the components added to the triple-pane windows limit the transfer of heat.
Thinking about new energy efficient replacement windows for your home? Stanek vinyl replacement windows are more durable and stronger than typical vinyl replacement windows. Stanek vinyl windows are affordable, easy to care for, energy efficient, and are available in high-quality styles, colors and options to fit your budget.
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