Low-E Glass vs Double-Glazed Glass: Which Is Better?

August 16, 2024

Key Takeaways

Low-E glass has a microscopic coating that reflects heat, reducing energy bills by up to 30%.
Double-glazed glass consists of two glass panes with a space between them, offering excellent insulation.
Low-E glass is better for controlling solar heat gain, while double-glazed glass excels in overall insulation.
Choosing between Low-E and double-glazed glass depends on your climate, budget, and energy savings goals.
At Panda Windows & Doors, we provide customized glass solutions based on your personal preferences and the architecture of your home.

What is Low-E Glass?

Coated with a practically invisible layer of metallic oxides, low-E glass acts as a sunscreen for your house, blocking harmful UV rays and unwanted heat while letting in the sunshine.

Low-E glass is a simple yet smart way to control your indoor climate without cranking up the heater or air conditioner.

Advantages of Low-E Glass

It slashes energy costs because your HVAC system doesn’t have to work as hard.
It protects your furniture and curtains from fading due to UV rays.
It improves the comfort of your home by eliminating “cold glass” and reducing drafts.

Disadvantages of Low-E Glass

It can be more expensive than regular glass upfront.
In some climates, it might block too much solar heat, leading to higher heating costs.
Its performance can vary depending on the direction your windows face.

Here’s how Low-E glass regulates at-home temperatures during summer and winter. (image courtesy of Prestige Plus).

Founded in 1991, Panda Windows & Doors specializes in state-of-the-art custom glass wall systems for both residential and commercial spaces through Panda Windows & Doors. Operating from our manufacturing facility in Las Vegas, Nevada, we have been at the forefront of innovation for over 30 years. Our extensive product lineup includes over 80 high-end offerings, such as pivot doors, French doors, folding doors, lift & slides, multi-slides, horizontal sliding walls, and operable windows. These systems are available in materials like aluminum, steel, stainless steel, bronze, solid wood, and aluminum-wood clad.

We are renowned for our award-winning designs, engineering solutions, and fast lead times, delivering in just 6-10 weeks to customers throughout the U.S. and Caribbean. Trusted by leading architectural firms and glaziers nationwide, we stand as the premier manufacturer of custom luxury windows and doors in the United States.

Explore Custom Solutions from Panda Windows & Doors Today

What is Double-Glazed Glass?

Two sheets of glass with a space in between – that’s double-glazing. It’s exactly the same principle behind having two layers of clothing; it keeps you warm by trapping air in the middle.

Double-glazed glass consists of two panes of glass separated by a spacer and sealed together. This space is often filled with inert gas, like argon, to further improve insulation.

Advantages of Double-Glazed Glass

It offers superior insulation compared to single-pane windows.
It’s great for noise reduction, making it ideal for homes in busy areas.
It reduces the amount of condensation that forms on your windows.

Disadvantages of Double-Glazed Glass

Despite its benefits, double-glazed glass isn’t perfect:

It can be costlier than single-pane windows, both in terms of materials and installation.
Improper installation can lead to issues like fogging between the panes.
It’s heavier, which might require adjustments to your window frames.

A diagram of a double-glazed window.

A diagram of a double-glazed window (image courtesy of The Spruce).

Low-E Glass vs Double-Glazed Glass

Energy Efficiency

Low-E and double-glazed glass are both designed to improve your home’s energy efficiency, but achieve it in different ways.

Low-E glass focuses on reflecting heat while double-glazing is all about insulation.

Low-E glass is particularly effective at reducing cooling costs in the summer by reflecting heat away from your home.

On the flip side, double-glazed glass excels in the winter, keeping warmth inside.

Cost Considerations

While Low-E glass might be lighter on your wallet initially, double-glazed windows could offer more bang for your buck in the long run, especially in colder climates. The upfront investment may be higher, but the reduction in heating costs can make up for it over time.

Installation and Maintenance

Proper installation is crucial for the performance of both Low-E and double-glazed glass. Incorrect installation can lead to issues like drafts, leaks, and even structural damage over time. At Panda Windows & Doors, we recommend having a professional handle the installation to ensure optimal performance and to avoid any future headaches.

Both Low-E and double-glazed windows are relatively low maintenance. Regular cleaning and occasional inspections for seal integrity should keep them in top shape. However, if the seal on a double-glazed window fails, it can lead to condensation between the panes, which is a problem you won’t face with Low-E glass.

Aesthetic and Practical Considerations

Both Low-E and double-glazed glass can be tailored to look great. They come in various styles and can be made to fit the aesthetic of nearly any home – and they both reduce UV rays, which helps protect your furniture and floors from sun damage.

Ideal Uses for Each Glass Type

The choice between Low-E glass and double-glazed glass mostly boils down to climate, budget, and location. Let’s look at where each type excels.

Best Situations for Low-E Glass

Low-E glass is ideal for:

Homes in sunny climates where cooling costs are a primary concern.
Areas with mild winters, where the loss of passive solar heating isn’t a big issue.
Windows that get a lot of direct sunlight, to prevent UV damage to interiors.

Low-E glass isn’t just for windows; it’s also great for:

Skylights, to enjoy natural light without the added heat.
Greenhouses, to keep plants warm without overheating.
Display cases, to protect valuable items from fading.

A skylight made from Low-E glass.

Best Situations for Double-Glazed Glass

Homes in colder climates, where insulation from the cold is crucial.
Noisy urban or suburban areas, as it provides excellent soundproofing.
High-humidity environments, to reduce condensation and the risk of mold.

CONSIDERATION	LOW-E GLASS	DOUBLE-GLAZED
Energy Efficiency	– Blocks solar heat gain in summer, reducing cooling needs – Can block desirable solar heat gain in winter, potentially increasing heating costs – Provides good insulation, reducing heat loss by up to 30-50%	– Provides superior overall insulation and energy efficiency compared to single-pane Low-E – The air/gas gap between panes acts as an insulating barrier, reducing heat transfer in both directions
Cost Considerations	– Lower initial purchase and installation cost compared to double-glazed units – Long-term energy savings can offset higher upfront costs	– Higher upfront cost for full window replacement, but greater long-term energy savings and cost recovery over time
Installation and Maintenance	– Can be installed as a single-pane retrofit on existing windows – Low-E coatings are durable and less prone to seal failure	– Requires full window replacement during installation, more labor-intensive – If seal fails, entire unit may need replacement
Aesthetic and Practical Considerations	– Slightly tinted appearance can reduce visible light transmission compared to clear double-glazing – Provides better UV protection and prevents furniture fading	– Provides better soundproofing and noise reduction compared to single-pane Low-E glass – Clear appearance with no tint
Best Situations to Use	– Hot climates prone to overheating, to block solar heat gain – Retrofitting existing single-pane windows without full replacement – When on a limited budget but want to improve energy efficiency	– Cold climates or heating-dominated buildings, to maximize insulation and reduce heat loss – When you have the budget for higher upfront costs of full window replacement – If superior noise reduction is a priority

Comparison table between Low-E glass and double-glazed glass.

Making the Right Choice with Panda Windows & Doors

At Panda Windows & Doors, we work with you to understand your specific requirements – from maximizing energy efficiency to improving your home’s aesthetic or enhancing indoor comfort.

With our extensive range of customizable options, we’ll help you find the right fit for your home’s style and your personal preferences.

The Panda Process

1. Design: We help you choose the right custom luxury glass doors and windows from our 80+ options.

Tailor every detail, including glass types like Low-E or double-glazed glass.
Review and approve your sales order to ensure all specifications are correct before manufacturing.

2. Manufacturing: Our project manager confirms all necessary components and orders any unique materials. CNC machines precisely cut and mill extrusions. Extrusions are then thoroughly cleaned and powder-coated for a durable finish.

3. Quality Control: Each product undergoes rigorous inspection and testing on our Test Wall. We ensure smooth functionality and quality, providing you with photos and videos of your products before packaging.

4. Packaging & Shipping: Products are wrapped in protective materials and placed in custom-built crates for safe transit. We ensure your order arrives intact, whether shipping domestically or internationally.

5. Delivery & Warranty: Inspect your order upon arrival and register the product to activate the Limited Warranty. Apply a high-quality finish to wood surfaces within 7 days to prevent damage.

6. Care & Maintenance: Follow our care and maintenance guide to keep your Panda products in top condition. Regular cleaning and maintenance will ensure a lifetime of use and beauty.

Frequently Asked Questions (FAQ)

Does Low-E or Double-Glazed Glass Have a Better ROI?

Low-E glass is particularly effective at reducing cooling costs in warmer climates, while double-glazed glass excels in retaining heat during colder months. The best ROI for you will depend on your specific climate and the energy costs associated with it.

Most importantly, the improved comfort and potential increase in property value that come with installing high-quality glass should not be overlooked when considering ROI.

Can I Combine Low-E and Double-Glazing for Maximum Benefit?

Yes, you can combine the benefits of Low-E coatings with double-glazed glass to create windows that offer superior energy efficiency, so you get the best of both worlds: reduced heat transfer and excellent insulation. It’s an ideal solution for those looking to maximize energy savings and comfort in their home.

However, the combined benefits come with a higher upfront cost, so it’s important to consider your long-term savings and priorities.

How Does Weather Affect the Effectiveness of Low-E and Double-Glazed Glass?

Low-E glass performs best in areas with high solar heat gain, as it reflects unwanted heat away from your home. Conversely, double-glazed glass is most effective in cold climates where insulation from heat loss is crucial.