In commercial applications, laminated glass is a popular choice for its durability and safety features. But there are times when alternatives such as polycarbonate may be more suitable.
In this article, we’ll explore the differences between laminated glass and polycarbonate glass substitutes in terms of strength, cost-effectiveness, and other factors. We'll also discuss why each material type might be preferred for different uses in commercial buildings.
By better understanding these distinctions, you can make an informed decision about which alternative best suits your project's needs – laminated glass vs. polycarbonate.
Laminated Glass & Glass Alternatives
Both laminated glass (LG) and glass substitutes have their advantages over traditional glass. Polycarbonate and acrylic sheets are frequently used as substitutes for traditional glass. Considered “plastic glass,” both are suitable substitutes for many regular glass applications and offer improved security and public safety.
Let’s compare LG and polycarbonate (PC) in terms of their:
- Material Fabrication
- Glass Strength
- Impact Resistance
- Commercial Uses
Material Fabrication
Laminated glass is a type of safety glass made by bonding two or more panes together with a clear interlayer. Typically, the interlayer is made of polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), or SentryGlas® Plus (SGP).
For example, EVA film is preferred for exterior applications because it’s hydrophobic and resistant to water damage. It lasts longer than PVB and does not delaminate. TPU is a more flexible interlayer that increases a piece’s impact resistance.
Fabricators cut custom laminated glass panels to size and polish their edges based on customer specifications. To create finished pieces that fit your vision and project space, laminated glass can be fabricated with edgework, cutouts, shaping, and V-grooving. Since most vendors keep LG in stock, it’s a quick solution for projects that need safety glass.
Polycarbonate, a thermoplastic, is typically produced by injection molding or extrusion.
Injection molding involves forcing molten PC into a mold at high pressure, while thermoplastic extrusion requires melting PC pellets and pushing them through an opening to form long tubes or sheets.
PC is formable both at room temperature and when heated. Manufacturers use press brakes to re-form polycarbonate sheets and heat them to a low temperature to set the shape. It’s also recyclable. You’ve probably talked about both materials by their brand names. Polycarbonate sheets are often referred to as “Lexan,” and acrylic as “Plexiglass.”
Strength & Impact Resistance
While laminated glass is durable, it’s not as strong as polycarbonate. Compared to glass, polycarbonate sheets are up to 250 times stronger, while acrylic sheets are 17 times.
Polycarbonate sheets are extremely impact-resistant and nearly unbreakable. They can withstand multiple hits from high-velocity projectiles, making them ideal for security applications. Polycarbonate sheets are extremely impact-resistant and nearly unbreakable. They can withstand multiple hits from high-velocity projectiles, making them ideal for security applications. However, both LG and PC are considered commercial safety glass.
Unlike traditional glass, which shatters into sharp pieces when broken, polycarbonate is designed to absorb impact energy and deform without breaking. When LG breaks, the interlayer holds the majority of the glass pieces bonded to it in place, keeping the pane mostly intact.
This means that even if struck with high force, neither LG nor PC will create dangerous shards that could cause injury.
Commercial Uses
Because of its strength and safety, laminated glass is the first choice in many commercial applications:
- Automotive glass
- Storefronts
- Skylights
- Sliding doors
- Glass railings
- Display cases
- Soundproof booths
- Bulletproof glass
While also strong and shatterproof, PC is preferred in applications where cost and weight are factors.
Commercial polycarbonate uses include:
- Bulletproof windows
- Roofing
- Greenhouse panels
- Outdoor equipment windshields
- Windows
- Partitions
Selecting the right glazing material involves more than comparing strength and cost. Project requirements, maintenance expectations, code considerations, and long-term performance all play a role in determining whether laminated glass or polycarbonate is the best fit.
For many commercial glazing applications, laminated glass provides an ideal balance of safety, durability, and performance.
Advantages & Disadvantages: Laminated Glass vs. Polycarbonate
Both LG and PC are great choices for strong, durable commercial safety glasses. However, each has its pros and cons.
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Weight Differences
Laminated glass is generally heavier than its polycarbonate substitutes. The exact weight depends on the number of layers, but typically, laminated glass weighs roughly 3 to 4 pounds per square foot. This is around 2-3x heavier than polycarbonate, which typically weighs just 1.5 pounds per square foot.
Polycarbonate vs. Glass Cost
Laminated glass is more expensive than polycarbonate substitutes. On average, laminated glass costs about 2-3x more than polycarbonate. This is due to the additional materials and manufacturing process it requires.
However, polycarbonate has its disadvantages as well. What you save in weight and cost, you pay for with less clarity and fewer “uncoated” benefits.
Design Considerations: Aesthetics and Visual Performance
While both materials provide safety benefits, visual appearance often becomes the deciding factor in architectural applications.
Laminated glass delivers exceptional optical clarity and maintains its appearance over decades of service. Polycarbonate offers outstanding impact resistance but can be susceptible to scratching and may experience discoloration over time without specialized coatings.
For projects where transparency, daylighting, and architectural aesthetics are priorities, laminated glass is often the preferred choice.
Durability & Surface Finish
PC is prone to scratches, diminishing its overall aesthetic. It discolors over time due to UV exposure. Whereas LG is UV-resistant thanks to its interlayers, PC requires a special coating to achieve UV resistance. Coatings are also available to increase PC’s scratch resistance – but of course, adding coatings to PC increases its overall cost as well.
Fabrication Process
The fabrication process for PC offers advantages over laminated glass. This flexibility allows contractors to find custom solutions that perfectly match the needs of their project.
Shaping Polycarbonate
Polycarbonate can be easily cut with a variety of tools, making it faster and easier to install than laminated glass. It's also much simpler to work with when creating intricate designs or patterns. Overall, polycarbonate glass offers numerous benefits, making it a great option for contractors seeking an affordable, versatile material that can be quickly and easily cut into custom shapes. Its lighter weight makes it easier to transport and install than laminated glass, while its lower cost means contractors don't have to sacrifice quality when sticking to a tight budget.
Which is Best for Your Project?
There is no one-size-fits-all answer when comparing laminated glass and polycarbonate. The right choice depends on the project's performance requirements, design objectives, budget, and installation considerations. Polycarbonate excels in high-impact and lightweight applications, while laminated glass remains the preferred solution for many commercial glazing systems due to its clarity, durability, acoustic performance, and long-term appearance.
Working with an experienced glass fabricator early in the design process can help project teams evaluate options and select the best material for their specific application.
