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Replacement Double Pane Glass Information

Failed double pane glass unit Seattle Beacon Hill Glass
Failed Double Pane Glass Unit

Beacon Hill Glass your all-inclusive resource for replacement double pane glass and insulated glass unit solutions designed for different climates. The type of glass you choose can significantly affect your home’s energy efficiency, comfort and overall market value.

We will explore ways to elevate your energy savings and explore low-emissivity (Low-E) glass options. We’ll also navigate through various shapes, tints, patterns, and grids to satisfy your aesthetic needs.

What You Should Know About Double Pane Glass

Double pane glass units consist of two panes of glass held apart at an equal distance by a spacer, then sealed on the edges. 

Insulated glass units (IGUs) are essentially a unit comprising two glass sheets separated by a central spacer and hermetically sealed around the edges. These insulated glass units elevate your home’s comfort level, diminish energy consumption, and reduce noise pollution from the outside world.

When paired with low-emissivity or Low-E glass, they offer additional protection against damaging ultraviolet light, safeguarding your flooring and furniture. Double pane glass is a standard in some areas requirement to comply with all building and energy codes.

Information on how low-E works
How Low-E Works

While these insulated glass units are robust, they’re not invincible. Often the seals will fail which leads to foggy or condensation moisture filled glass. The seals in these double pane glass can become vulnerable over time compromised due to various factors: 

  • UV rays

  • Moisture

  • Temperature swings

  • Age

  • Accidental damage


Elevate Your Home's Efficiency:

Double pane windows already do a fantastic job of bolstering energy efficiency, thanks to their dual layers of glass separated by a cushion of air. This insulation layer significantly diminishes the outside temps that seep through the glass, making your home cozier in summer and winter. The added benefit? You can comfortably stabilize your thermostat settings, increasing energy savings and simplifying smart home management.

The Triple-Pane Glass: An Older Solution with a Niche Use

In years past, triple-pane windows were all the hype for those looking to maximize energy efficiency and comfort. Adding an extra pane, they feature three layers of glass, with two insulating air spaces in between. However, advancements in other energy-saving techniques have relegated triple-pane windows to a less common option when looking to replace glass.

That said, triple-pane windows do come with some caveats. They’re notably heavier and more challenging to operate, often needing a more robust window frame and construction.

Understanding Low-E Glass:

Low-E glass, or Low Emissivity glass, is a marvel of thermal performance. In cooler climates, this specially engineered replacement glass acts as a mirror for heat, reflecting it into your interior spaces. Meanwhile, it works the opposite way in warmer environments, deflecting heat out. Beyond its thermal properties, Low-E glass offers partial UV protection, meaning it’s a guardian for your comfort and furnishings.

Hard Coat vs. Soft Coat:

There are two kinds of a Low-E coating on glass, hard coat and soft coat. Hard coat LowE is manufactured by depositing a microscopically thin metal layer onto the glass. This variant is notably durable and excels at harnessing passive solar heat transfer. It’s often the more budget-friendly choice as well.

On the other hand, soft-coat Low-E glass receives its coating after manufacturing. Though less durable, it provides superior insulation and is generally used for windows rated by the Home Energy Rating System.

Local Building Codes and Low-E Glass

Local building codes may demand more stringent energy efficiency standards than Energy Star requirements. In such cases, double-pane windows with soft coat Low-E glass could be an effective alternative compared to standard clear glass without any special coatings.

Additional Notes on Low-E Glass:

Light and Space: The VLT Factor

Visible Light Transmittance (VLT) is a crucial consideration. This metric measures the light your windows allow to pass through. If you desire luminous living spaces, you’ll need a higher VLT. For example, super-clear low-iron single-pane glass can offer a VLT exceeding 90, while heavily tinted versions might register as low as 10.

UV Protection: More than Just Sunblock

Lastly, it does offer a degree of UV protection, which is especially beneficial if you have sun-sensitive items like artwork, flooring, or furniture. Opting for insulated glass with enhanced UV protective features can help preserve these items for many years.

Argon and Krypton Explained

Working to enhance the energy efficiency of double pane windows, Argon gas and Krypton gases are contained in the vacuum of an insulated glass window. Some super efficient Krypton gas filled windows are gaining attention for their superior thermal properties, but whether the extra cost is justified remains a topic of discussion. Mixed gases or pure Argon gas are popular choices for filling the void between the panes in replacement glass, offering a balance of thermal and acoustic insulation at a more accessible price point.

The Longevity of Gas Filled Units

It’s worth noting that even the most durable seals can experience slight gas leakage over time. However, comfort and energy savings far outweigh the incremental cost leakage. With proper sealing, you can expect energy efficient double-pane windows to retain about 90% of its original gas even a decade after installation.

Additional Avenues for Energy Efficiency

Spacers for insulated double pane glass units
Insulated Glass Spacers

Insulated Glass Unit Spacers:

The spacer in a window unit with two panes has a dual role: keeping the glass panes at a set distance and removing any incidental moisture. While essential, traditional spacers can slightly diminish the window’s energy efficiency. For those looking to match spacers with their existing windows, bear in mind that typical spacers don’t offer optimal insulation. Upgrading to warm edge spacers can be a game-changer for thermal performance.

Laminated Glass:

While we will discuss laminated glass, safety and security aspects later in this guide, it’s worth mentioning that laminated insulated glass is another option for enhanced energy efficiency. Stay tuned for more details in the sections to come.

Laminated glass - beacon hill glass
Laminated Glass

Design and Appearance Features:

As an industry leader in glass replacement, Beacon Hill Glass proudly offers window unit solutions tailored to residential and commercial needs. Our extensive suite of services encompasses custom shapes, precision engineered double pane glass units, safety and security glass options, skylight renovations, unique specialty glass varieties, historically accurate glass choices, intricate grid work, and comprehensive storefront and commercial glass solutions.

Door Code Requirement

Building codes have made it a requirement for all doors that are glass or have glass within to be safety, meaning the glass would have to be tempered glass or laminated, otherwise grandfathered in. While most doors can easily accommodate this upgrade, exceptions are exceedingly rare, this includes slider patio doors, entry and back doors, french doors, garage doors, shower, accordion doors & patio doors.

Tempered glass - beacon hill glass
Tempered Glass

Safety Glass and Security Glass

Passage doors, sidelites and window glass within 24” of the door and windows below 18" off the floor must use safety glass. Glass in a “wet” room must be safety glass which includes bathrooms with tubs or showers within five feet of a window. Most building inspectors will want all glass in a “wet” room to be safety glass, period. Windows larger than nine square feet may need to have safety glass depending on their location. 

Safety and Security:

Whether it’s a passage door, sidelight, or any window within 24 inches of a door, safety glass is non-negotiable. The same applies to “wet” rooms, like bathrooms with tubs or showers within five feet of a window. Most building inspectors will insist on safety glass for all windows in such spaces. Additionally, windows larger than nine square feet may require safety glass, depending on their location.

A Closer Look at Tempered and Laminated Glass:

When it comes to safety glass in double pane units, tempered glass is the go-to option. It’s four times stronger than traditional “annealed” glass and breaks into small, less hazardous pebble-like broken glass pieces. It’s a popular choice for many, economically priced and lightweight, with a standard thickness of 1/8″. Laminated replacement glass is another widely utilized option. Comprising two glass panes with a PVB (polyvinyl butyral) interlayer, laminated glass was initially designed for windshields and offers unique benefits. Laminated glass is difficult to penetrate, providing added security against break-ins, and is commonly used in storefronts to prevent “smash and grab” incidents. Moreover, laminated glass provides superior insulation, blocks up to 98% of UV rays, and significantly reduces noise. For a closer look into the advantages of safety glass, feel free to explore our dedicated safety glass page.

For more comprehensive information on safety glass and its benefits, visit our safety glass page.

Navigating the Specifics of Skylight Replacement:

When it comes to skylights, the stakes are exceptionally high, given that any broken glass from above could be catastrophic. Issues can arise from external objects like falling branches or birds striking the glass or internal problems such as seal failure leading to fogging.

Our replacement insulated glass skylights are meticulously engineered to combine tempered glass outside for added break resistance and laminated glass on the inside to hold the pane in place and block debris. For more insights on skylight glass, visit our website.

A Palette of Specialty Glass Choices

Double and triple-pane units offer various glass types tailored to your needs. You can opt for decorative or privacy glass on one side while incorporating low-E glass on the other for optimal energy efficiency. 

Adding a filling of argon gas gives you a glass unit that melds aesthetic appeal and functional prowess.

Double pane glass window grids
Window Glass Grids

Aesthetics Of Grids:

While they don’t impact functionality, the grids sandwiched between many double pane glass units add unique decorative flair. We can replace these grids or fabricate new double to match the existing grid in size, shape, and pattern. It’s important to note that we cannot incorporate custom requested color grids.

Solutions for Storefront and Commercial Spaces:

The glass requirements for commercial buildings are unique and often multifaceted. Whether you need laminated glass for enhanced security against a smash and grab break in or tinted specialty low-E glass for aesthetic and functional reasons, we’ve got you covered. Our team can provide a custom quote tailored to your needs.

Reach out to us today via phone or email with your questions. We’re committed to delivering exemplary service and high-quality insulated glass products that save money and guarantee your complete satisfaction.

Choose Beacon Hill Glass For All Your Replacement Double Pane Glass Needs

Whether it’s upgrading your windows to meet building codes, enhancing the aesthetic appeal of your home, or addressing specific needs like skylights and commercial glass. Beacon Hill Glass has you covered with customized solutions. Proudly serving all of Seattle, Washington and surrounding nearby cities through out King County. We offer quality products and impeccable customer service. With our expert advice and extensive range of services, making the right choice for your insulated glass replacement needs has never been easier.

Contact us today for a customized quote or to consult our team of experts. Let Beacon Hill Glass be your trusted partner in achieving the comfort, energy efficiency, and beauty you seek for your home or business. Reach us at or call and text message us at: 206.372.4186 to launch your project with confidence. Please visit our website for more information or products and services we offer. Thank you!


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