You would think this is a question easily answered, but I have often worked with homeowners struggling with this decision. There are a number of factors that should be taken into consideration, but with a little thought about where the blocks will be used, how they will be used, and how you want to install them, you will have no problem making the right choice.

Differences

Let's first talk about the biggest difference between the two products. Understanding this may be all you need to know to decide.

Glass Blocks

In addition to prefabricated, glass block windows and panels, glass blocks are also sold individually. Just like using wooden building blocks when you were a child, you can follow your imagination to its outer limits and construct just about any design you want with glass blocks.

Acrylic Blocks

Acrylic blocks are not sold as individual blocks. They are only sold as finished products like windows, transoms, and wall panels. If you want to construct your own design, acrylic blocks are not an option. However, if you are even considering a prefab unit, please read on.

If you hold a glass block window and an acrylic block window up next to each other, you probably won't know which is which. What's that? You can't hold up the glass block window? You've just discovered the next big difference, weight. Comparing products of equal sizes you will find that glass block pieces typically weigh 4 times as much as acrylic. That can be a major factor, depending on where you plan to install it. If you are doing a large piece in an interior wall the weight of glass may be a problem. If you are doing the installation yourself, you will definitely find the lighter weight of an acrylic block window much easier to work with.

Similarities

Surprisingly, whether you are considering acrylic windows, a glass block shower or any other installation made from either glass or acrylic blocks, you will find that if they are of similar size, the price will be about the same.

Appearance

The same is true of their appearance; there have been times that the only way I could tell the difference on an installed window was to tap on it. They definitely have a different sound but I've never seen someone use that to base their purchase on.

There may be minor differences in the actual block pattern, but for the most part, glass and acrylic block windows look interchangeable:

- Both are sold in 8" x 8" or 6" x 6" block sizes.

- Both come in vinyl frames, though some acrylic pieces are also offered in aluminum.

- Both obscure vision to some degree, depending upon the block style.

Basically you can't go wrong with either product. They are both attractive, suitable for various uses, quite strong, and very secure. Weigh the pro's and con's using our personal Pro's and Con's list below, find the right size, and enjoy the unique look that only a block window or partition can bring.

Summary of Pros and Cons

Pros of Glass Block

- Easy to clean

- Secure, much harder to break than standard windows

- Different sizes and shapes allow for endless design options

- Prefabricated windows and panels are available

- Different installation methods available

- 3" or 4" thicknesses available

- Less sound transmission than standard glass

- Twice the R-value of single paned glass windows

- Earthquake resistant

- Availability of specialty blocks (Hurricane, Fire, & Bullet resistant)

- Available shower kits with just about everything included

Cons of Glass Block

- Heavy, the average block weighs in around 5lbs.

- Large applications can be time consuming to install

- Non-load baring

- Non functioning as operable windows

Pros of Acrylic Block

- Lightweight

- Operable windows available as Casement, Hopper or Awning

- Secure, harder to break than standard windows or glass block

- Available for installation as windows, transoms, sidelights and walls

- Different frame colors are available

- Four color choices plus the standard clear

- Availability of Arch and Octagon styles

- Sealed to prevent condensation

- Preassembled panels that are easy to install

- As energy efficient as double paned traditional windows

- Tinted Energy Star rated Solar Block windows

Cons of Acrylic Block

- Available only as pre-fabricated unit

- Can be scratched (though not easily)

- Sensitive to harsh cleaning products

- Non-load baring