In this blog:
Low-E windows protect your home’s interiors from UV and infrared light, improving comfort and energy efficiency.
- Low-E window coatings reduce undesirable light entering your home without sacrificing natural light.
- By optimizing your home’s light, low-E windows help you maintain optimal interior temperatures year-round.
- Consistent interior temperatures reduce strain on HVAC systems and can potentially lower utility costs.
You deserve a beautifully bright, energy-efficient home. Low-E (low-emissivity) windows can help you get it by protecting your interior from unwanted ultraviolet (UV) and infrared (IR) light. They’re valuable assets for homeowners wanting to improve their home’s performance and comfort without sacrificing clear views. Read on to learn more about low-E windows and their benefits.
What Is Low-E Glass?
Low-E glass is window glass treated with a microscopically thin metallic coating that stops UV and IR rays attempting to enter your home. Visible light still passes through unaffected, providing your home’s daytime illumination. Low-E glass can be installed in virtually any window style, from traditional double-hung windows to custom designs.
How Do Low-E Windows Work?
In simplest terms, low-E windows work by catching and deflecting UV and IR light while allowing natural light to pass. The process functions somewhat similarly to applying sunscreen.
To better understand low-E windows, it helps to understand how light itself works. The sun emits a broad spectrum of light, which is divided into three main types:
- Ultraviolet (UV) light: Low-frequency light invisible to the human eye.
- Visible light: The light we see, which manifests as the color spectrum.
- Infrared (IR) light: High-frequency light that’s invisible, but that we feel as heat.
In homes with standard window glass, broad-spectrum light can stream freely inside. Unfiltered UV and IR rays can heat your home’s interior faster, making it uncomfortable and increasing the burden on your HVAC systems. They can also damage furniture, carpets, upholstery, artwork and other decorations. Low-E windows lessen these risks by keeping more of the harmful light outdoors where it belongs.
What Are the Benefits of Installing Low-E Windows?
As they work to keep UV and IR rays out of your home, low-E windows balance and optimize your home’s heat and light gain. This provides multiple benefits, such as:
- Better interior temperature control: Low-E windows help keep interiors cooler in summer and warmer in winter, making living spaces more pleasant.
- Improved HVAC performance: By managing your home’s interior temperatures, low-E glass reduces demand on heaters and air conditioners, creating potential energy savings.
- Protection for interior decorations: Without constant exposure to UV rays, household furnishings resist fading and light damage.
Are Low-E Windows Energy-Efficient?
Low-E windows have become a popular home upgrade primarily because of their energy efficiency benefits. The Lawrence Berkeley National Laboratory (LBNL) notes that installing low-E windows can:
- Reduce household energy loss by up to 40%
- Keep up to 70% of heat outside in summer and inside in winter
- Cut UV light damage by up to 75%
LBNL also estimates that low-E windows deliver $1.3 billion in annual residential energy savings for American homes. These savings can add up over many years of use, providing valuable relief for your wallet across all seasons.
Choosing the Right Low-E Windows for Your Home
Low-E glass is often one of several built-in energy-efficiency components within modern windows. Other items may include multi-pane designs, argon gas inserts and durable weatherstripping. As you search for the right windows, you’ll want to weigh each feature carefully.
Various helpful energy efficiency ratings can help you compare your options:
- Solar Heat Gain Coefficients (SHGC): The SHGC measures how much solar radiation passes through glass and enters your home as heat. The lower the SHGC, the less heat enters your home.
- U-Factors (U-Values): U-Factors measure heat flow through an object. A window with a lower U-Value allows in less heat.
- R-Values: R-Values measure how well a window’s insulation keeps heat in or out of your home. The higher the R-Value, the better the insulation.
- Visible transmittance (VT): Your VT rating indicates how much visible light your windows allow in. A higher VT means more light enters your space, but it can also allow more heat inside.
- Air leakage (AL) values: AL ratings measure how well your home’s products prevent air escape. The lower the rating, the less energy escapes.
When selecting windows, the goal isn’t to choose the lowest or highest energy ratings. Aim for the best fit for your home, which may vary depending on factors like your local climate and the direction your windows face.
The best way to find the right window choice is to work with experts who can help you compare options based on your specific circumstances. It’s also essential to have your windows professionally installed, which helps prevent flaws that may affect performance.
Learn More About Window World’s Low-E Windows
If you’re ready to upgrade to more efficient windows, Window World’s ENERGY STAR®-certified replacement windows are second to none. Enjoy high-performance low-E glass and other features that improve comfort, protect interiors and reduce energy waste.
Get a free quote on your next window upgrades and get ready to love your home even more.
FAQs About Low-E Glass
Do low-E windows require special cleaning?
Cleaning low-E windows doesn’t require any exceptionally special care. However, you’ll want to avoid anything that could damage or scratch the window’s reflective coating. For best results, dilute a small amount of dish soap in warm water and clean the glass using a damp microfiber cloth. Wipe dry with a soft, clean towel.
Does low-E glass block natural light?
Low-E glass has little to no effect on natural light and is not the same as tinted window glass. The microscopic coating is clear and virtually colorless, allowing natural light to flow easily into your home with minimal interruption.
Can houseplants grow near low-E windows?
Yes, houseplants can grow near low-E windows. The reflective coating doesn’t affect the natural light that plants need.
If you’re looking for windows ideal for nurturing plant life, garden windows or bay and bow windows are perfect for making sure your plants receive plenty of sunshine.
What is the lifespan of low-E glass?
Quality low-E glass is designed to last as long as the window’s service life. Damage to the glass or window frame may shorten this lifespan, while improper maintenance can also affect the low-E coating. Always follow your windows’ recommended care practices to minimize the risk.