Why You Should Avoid Glass Block Windows

Glass block windows may have been a staple in older buildings with outdated style, but some modern builders are giving them a little comeback in newer homes.

glass block windows

Why are glass block windows used, and are they a good choice for a home? Here are a few reasons why you should avoid glass block windows.

What Are Glass Block Windows?

Glass block windows came into fashion around the early 1900s as a durable and insulating way to let natural light into factories. We still use them today: not only for windows, but also for walls and skylights.

Some people like to use them for bathroom walls and windows, as they let in light but nobody can see inside. When built into “walls”, they are laid in a grid with steel-reinforced mortar in between each block. They can be made to be durable against bullets and fire.

However, frosted and decorative glass windows can do the same thing without making your home look outdated. They basically make glass block windows obsolete.

Are Glass Block Windows Attractive?

While beauty is in the eye of the beholder, many current design experts, home decorators and architects agree that the look of glass block is outdated, unattractive and unnecessary.

Some architects have argued that glass block is all too commonly relied upon as a crutch to cover up a poorly designed walkway or corner. A better material could’ve been used if the builder had wanted to spend the time and money.

Glass block windows have a thick, cloudy, and slightly reflective look that is difficult to see through, and some homeowners prefer to let this trend stay in the past.

Glass Block Windows Are Tough to Construct

Glass block windows aren’t a fit for a beginner or for your average DIY project. They must be carefully planned and measured out, and the blocks must be cut to size. The process is fairly similar to bricklaying, which is a learned skill best performed by a professional.

If the blocks are not laid and sealed properly, you’re looking at damage not only to the windows but to the rest of your house as well, thanks to potential water leakage. It’s possible to find pre-laid sections of glass block, but they’re extremely heavy and will require at least one other person to help you lift them.

Are Glass Block Windows Tough?

Glass block walls are often touted for their strength. However, their thickness and durability have tricked some homeowners into thinking they can bear more weight than they really can.

Glass block windows should never be used in any load-bearing capacity. They may not break immediately, but given enough time they will start cracking, which is a safety hazard and an expensive mess to clean up.

Additionally, glass block windows are quite heavy, so you would also need to inspect the floor under the area, and possibly add structural support boards underneath. The weight of a glass block wall or large window could cause the floor to sink, warp or even collapse.

Can You See Through Glass Block Windows?

glass block

Glass block windows are commonly used as a solution to privacy in home design – especially in bathrooms, where you need to have adequate privacy.

Many assume that the cloudy or frosted nature of a glass block is enough to block out the view for passersby, only to find out after the costly and time-consuming installation that the neighbors have been getting a peep show.

An onlooker probably won’t be able to see every detail up close and personal, but some homeowners have complained of having to put up curtains in order to prevent others from seeing full outlines, skin coloration and other personal details they’d rather not show off.

Glass Block Windows Don’t Allow Ventilation

Ventilation is an important feature in any home – not only do we enjoy fresh air for a pleasant atmosphere, but it’s actually essential to our health as well.

We need to be able to open the windows when someone is ill, when we’re cleaning something with harsh chemicals or doing a home project such as painting or varnishing. Otherwise, the fumes could be dangerous to our health.

Being able to open the windows in any given room also helps us save money – if we can’t let in a little air when the weather changes, we’ll have to turn on our furnace or air conditioner more frequently. This will end up costing you more on your energy bills each month.

Glass Block Windows Are Expensive

Glass block windows are heavy and the process used to create them is expensive, so they can be a costly addition to your home when compared with the standard alternatives.

Even for a tiny basement window constructed from glass block, it would cost at least $175. A single glass block would cost approximately $15, with specialty blocks such as frosted or colored blocks can run up to $50.

Additionally, you’d need to secure help for installation and have them re-sealed every so often to prevent water from seeping through.

Glass Block Windows Are Unsuitable for Warm Climates

If you live in an area where the summers are very hot, such as the Midwest, you may wish to reconsider putting glass block windows in your home. Glass blocks absorb and transfer the heat very well, turning your room into a greenhouse.

You’ll spend more money and energy on air conditioning to offset these effects, which are more pronounced in a small area such as a bathroom. Many homeowners have complained about their bathrooms developing a stifling heat during the day after installing glass block windows, even when the air conditioner is running.

If replacing your glass block windows isn’t in your immediate plans, here are some helpful ways you can help combat energy drains in the home right away:

  • Improve your thermostat to a smart thermostat and create schedules to use less energy
  • Replace any air filters
  • Check for leaks in the bathroom – toilet, sink and shower areas
  • Check your home’s insulation
  • Make sure you’re using the best utility service available to you

Stay Away From Glass Block Windows

So, should glass block windows remain in the past? Some designers think that they can be used to great effect in modern designs and improve the look and value of a home and we disagree.

If you are considering working with this material, you may want to second guess that. Other window styles and accessories offer the same features as glass block windows without the outdated look.

If you do have glass block windows and want to replace them with something better and beautiful, look no further than Feldco for the best replacement windows in the Midwest.

With over 400,000 happy customers, we know what it takes to improve your home’s energy efficiency and curb appeal. Get started today with a free quote online and see why so many homeowners trust us.

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