Do Glass Block Windows Insulate

Do Glass Block Windows Insulate

Some age-old architectural structures stand the test of style trends and preferences. While glass block windows may receive some abuse for being outdated, this controversial choice offers a unique aesthetic. Today, many architects favor this material for its features, including its light-welcoming ability and energy efficiency. From extravagant homes↗ to commercial↗ spaces, glass bricks have made a comeback. But, are they the right choice for insulation?

The argument for glass blocks is not clear cut. Making an informed decision for your build requires you to understand the other insulating options on the market and choosing the best look and function for your space.

In this post, we'll cover the following topics:
(Use the links below to jump ahead)

What are Glass Block Windows?

Glass block windows are a nod to a trend of the early 1900s style. Arch Daily↗ describes it as "a glass architectural element that admits light while maintaining visual privacy due to its translucent properties." 

Glass bricks are usually two to three inches thick and are created by fusing two pieces of glass and leaving the center hollow. It was initially built as a durable and insulating window option for factories. Many old homes will still have these old-fashioned glass window blocks in bathrooms or as room dividers that allow light through. 

Glass block windows come in a variety of sizes, colors, and patterns. They are installed in a similar way to bricks and mortared with glass-suitable grout or silicone. Vinyl, composite, or other materials frame each glass block.

What are Insulating Windows?

Insulated windows reduce the amount of heat transferred from one side of the glass to the other. When homes are built, roofs and walls are often made with layers of insulation. Windows, however, need to be upgraded to provide valuable insulating properties. Today, there are numerous window options that will help to keep your dwelling warm in winter and cool in summer. Insulating windows contribute to energy efficiency and save you money in the long run. 

Single pane windows are unhelpful in insulating your home or office. The alternative is to go for multipane windows - double, triple, or quadruple-pane windows, which have gas fixed into the frame to assist with energy efficiency. Choosing a multipane option will depend on your local climate and budget.

There are some DIY insulating projects and products↗ out there, but none will be as effective as the use of insulated glass units. 

Do Glass Block Windows Insulate?

Windows with more than one layer of glass offer insulation. Therefore, glass block windows will offer better energy efficiency than single-pane windows due to their double use of glass. Modern glass blocks also use pressure controlled argon gas↗ inside the block. This gas gives a reduction in heat transmittance. Low emissivity glass can also be used in the creation of modern glass bricks, assisting in filtering UV light. 

With glass blocks, the mortar that holds them in place also eliminates the filtration of the air from one side to the other. Their airtight ability reduces drafts and heat transference. While glass blocks are known for their ability to offer privacy because of the various pressed patterns in the glass, the patterns also deflect and diffuse natural light. 

Should I Get Glass Block Windows?

Glass blocks offer many benefits. However, they are not to be used in spaces that need ventilation as the windows cannot open. This makes them perfect for skylights or passageways that want to allow natural light in, all the while offering privacy. Glass blocks are also an excellent choice for upgrading the security in your home as they are almost indestructible. 

The Benefits of Glass Blocks

  • added security
  • fire-resistant
  • provides privacy while still allowing light through
  • soundproofing
  • bullet resistant
  • waterproof and airtight
  • energy efficient

The Downside of Glass Blocks

  • They're heavy and may need structural support
  • No ventilation
  • Sometimes they need resealing and maintenance

Seeing Clearly in Your Decision-Making

Glass bricks are an excellent choice for the right space. They offer privacy and energy efficiency, all while allowing natural light to pass through still. Many will agree that glass bricks are aesthetically pleasing and offer curb appeal. So whether you are embracing the old features of your historic home, or you're looking for a divider for your office space, glass bricks offer versatility that traditional clear glass cannot.


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