Glass Block Windows Guide: 3 Pros and Cons to Consider

Updated June 21, 2022
The interior of a modern kitchen with glass block windows and wooden cabinets
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Glass block windows not only look great, but they also offer added security and energy efficiency

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Your home may be your castle, but adding glass block windows can make it look like one. But glass block windows aren’t just attractive, they’re also highly energy-efficient and offer great security. Still, though you may have seen these features in other people’s homes, you may not have known what they were called or the benefits they have. We’ll show you the pros and cons of glass block windows.

Pros and cons of glass block windows, including that they are energy efficient but costly

What Are Glass Block Windows?

Glass block windows can usually be found in basements and bathrooms, but they can be installed pretty much anywhere. Instead of traditional windows, which are usually made of a single pane of transparent glass, glass block windows are made of multiple blocks of thick glass inset into a window frame. These thick glass blocks let light flood into the room, without allowing you to see through them. So you get tons of both natural light and privacy.

3 Pros of Glass Block Windows

Glass block windows have a whole lot going for them, especially if you choose to install them in your basement, bathroom, or ground floor windows.

1. Energy Efficiency

Glass block windows provide greater energy efficiency, with some factory-built glass block windows meeting federal Energy Star efficiency guidelines. To identify these highly efficient windows, just look for the Energy Star designation on the glass. 

Most standard glass block windows are about as efficient as thermal-pane windows, twice as efficient as single-pane, and are airtight. Some glass block windows also have low-E glass properties, meaning they are able to reduce the amount of heat lost through the window.

In addition, glass block windows are also noted for their remarkable ability to let light into even the darkest of spaces, saving on the energy costs associated with lighting basements and other dark areas.

You can also vent your glass block windows to allow for airflow, further increasing energy efficiency by reducing cooling costs.

2. Enhanced Aesthetic Appeal

Glass blocks aren't just great for exterior windows. They can also offer a dramatic, upscale look for shower doors, wet bars, garage windows, partition walls, and large exterior windows.

Homeowners can choose from several designs, patterns, colors, and even customized etchings.

The most common glass block projects, though, are more practical in application, like basements and bathrooms. Installing glass block for exterior windows can greatly enhance the curb appeal of your home, offering a unique alternative to traditional glass panes.

3. Increased Protection and Security

Glass block windows are especially useful for basements and first floor windows because they are very hard to breach. They’re made of masonry and that means they’re nearly impossible to remove. 

Because glass block windows are so secure, they’re also great at sealing your basement from flood damage. That’s why homeowners are increasingly turning to glass block to make their basement windows not only more secure but also virtually waterproof.

3 Cons of Glass Block Windows

The interior of a luxurious bathroom with glass block windows and a chandelier
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Installing glass block windows can enhance the privacy, style, and energy efficiency of any room. But while there are numerous benefits to glass block windows, there are also a few cons.

1. Cost

The cost of glass block windows is often slightly higher than that of traditional glass panes. You’ll pay anywhere from $500 to $1,000, including professional installation. Costs will vary, though, depending on the size of the job and your location.

2. Maintenance

To keep enjoying the energy-saving benefits of glass block windows, there are some steps you need to take to maintain your windows. You’ll need to have your glass blocks resealed every few years, something that is generally not necessary for solid glass pane windows.

3. Installation

To reap the rewards of glass block windows, it’s best to find a glass block installation company. That’s because glass block window installation can be trickier than with solid pane windows. In general, it’s better to have a pro preassemble the window and fit it into a precut frame than to try to build up the window into the frame block by block.

So if you’re looking to install the window yourself, the unique challenges of glass block will definitely be a con for you.

Consider if Glass Block Windows Are Right for Your Home

If you’re looking for an aesthetically appealing, energy-efficient, and highly secure window option, then glass block could be just the ticket. 

But if your preference is a low-maintenance, easy-to-install, and budget-friendly window, then a glass block window may not be the thing for you. Consider the pros and cons of this window type to decide what’s right for your budget and home.

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