What Types of Glass Are There?

When considering a glass railing system, there are four main glass types referenced: plexiglass, annealed glass, tempered glass, and laminated glass. Plexiglass is not actually glass, but a clear, plastic based sheet that is often used to cut down cost and take advantage of its flexible strength.Annealed glass is a term you would hear when searching for glass railing, but it is a softer form of glass that is not fit for safety use.

Tempered glass, or toughened glass, is the most common glass railing type and is created by strengthening glass through a heating and quenching process. Finally, laminated glass is the pinnacle of any glass railing. It is two tempered panels connected together with a middle vinyl layer, which creates a panel with peerless strength.

What is Acrylic & Plexiglass

The difference between acrylic glass railing and Plexiglass railing is the same as the difference between facial tissues and Kleenex(es). They are describing the same product, just using different names. Plexiglass is a brand of acrylic that eventually became the associated name for any clear acrylic panel.

Acrylic is a name derived from its more technical name polymethyl methacrylate. It is a clear, plastic based product that can be found almost anywhere.

Plexiglass is typically not the “go to” infill option for a project, but it usually ends up as a cost efficient substitute for a tempered glass railing. These two railings make up nearly every glass railing project installed. Plexiglass yields the same “see through” effect with a solid barrier at a cheaper cost. Depending on the quality and thickness, it can also provide incredible strength due to the amount of flex it can achieve. So, why doesn’t everyone use Plexiglass? While Plexiglass does offer a more cost effective solution, it has several disadvantages to a tempered glass panel.

Monolithic Glass

Monolithic glass is an overarching term used to describe a single, solid piece of glass. The three most common types of monolithic glass are: acrylic glass, annealed glass, or tempered glass.

A laminated panel would not fall under the monolithic label as it is constructed from two tempered panels with a vinyl layer in between.

Tempered Glass

A tempered glass panel is incredibly strong, and is what Viewrail Glass is made from. To make a tempered panel, annealed glass is cut to size and heated to over 1,100 degrees Farhenheit.When the panel is completely heated, it is then immediately quenched, or rapidly cooled, by high air flow on all sides.

The process of tempering is often used to help give metal alloys, such as steel, additional strength. Once the panel is quenched, it is considered tempered. Tempered panels are extremely strong and excel in a glass railing system.

Laminated Glass

Laminated glass can be made from different glass materials, but the general concept is a panel constructed from two panes of glass with a vinyl interlayer adhering the two panes together. Laminated glass railing is the strongest option as the interlayer allows the panel to flex and absorb an enormous amount of force.

While there are different lamination options such as PVB, EVA, or SGP, Viewrail typically recommends EVA for interior projects and SGP for exterior projects. SGP is incredibly resistant to UV and moisture damage, and is even rated for hurricane force winds. Laminated glass railing is most commonly found on coastal exterior decks, or commercial grade projects. Tempered glass panels vs. laminate glass panels

What is Annealed Glass?

Annealed glass is a form of soft glass and is not used for safety railing. It is typically found in table tops, windows, cabinet doors, or other similar applications. Annealed glass is often referred to as standard glass.To become annealed, the glass is thermally heated and heat-soaked until it reaches its “stress relief point,” which is between 850 and 900 degrees Fahrenheit.

Once glass achieves its annealed state, it can be cut or drilled without shattering.

However, at this stage it is not incredibly strong, and if it breaks it typically breaks into shards which can be dangerous. This is why the tempering process for glass railing is incredibly important.

Properties of Glass

UV Resistance: When considering a transparent railing solution, it is important that the barrier remains transparent. Since Plexiglass, also called acrylic glass, is technically a plastic, it begins to lose its transparency overtime when exposed to UV rays. It becomes cloudy or yellow and difficult to see through, which results in the need to replace the panels.

It’s likely you’ve seen this on headlights, or public transportation objects. The UV exposure will also break down or weaken the structure of the panel, weakening it and making it more susceptible to cracking.Glass, on the other hand, is nearly entirely UV resistant. This is why your house windows can remain clear after decades of use.

Scratching: Glass is extremely hard to permanently scratch. Typically, it takes an intention effort with a sharp object to scratch tempered glass. However, Plexiglass is relatively easy to scratch due to it’s softer plastic properties.

Once scratched, it is impossible to fix. If you think about headlights again, you can look and see a litany of overlapping scratches.

If your goal is a durable, transparent, and tough railing system, scratches and mars can easily detract from the appearance and presentation of your system.

Once again, after a while of use, it is possible Plexiglass panels would need to be replaced.

Cleaning: Let’s be honest, with either system some amount of cleaning is required. The same way you clean your house, or sweep your floors, or wash your car, is the same way every railing system requires a bit of maintenance to keep a great appearance.

As previously stated, Plexiglass is a plastic, and because of its chemical makeup certain household cleaners can actually react with the Plexiglass and damage it.There are specific cleaners for these types of panels.

The good news is: everyone knows how to clean glass and it’s hard to go wrong. There are many, many cleaners out there that would help clean and protect a glass panel.