Why We Prefer Acoustic Grade Glass (Laminated Glass) Over Plastic (Acrylic) for Soundproof Window Inserts

Customers often ask how acrylic window inserts (which are plastic) compare to acoustic glass window inserts (which are laminated glass).

Acrylic is Plastic

• Easy to manufacture (cuts easily)
• Lightweight (Reduces shipping costs, but lowers the ability to reduce noise.)
• Easy to scratch
• Discolors over time

“Acoustic-grade Acrylic”

Companies that offer “acoustic-grade acrylic” are actually offering 1/4″ thick acrylic instead of standard 1/8″ thickness. It would be more accurate to call it “double-thickness grade.” Doubling the thickness increases its ability to abate sound because the mass per square foot is increased, not because there are specially engineered characteristics of 1/4″ thick acrylic – it’s just thicker.

Acrylic Glass

Please note that the term “acrylic glass” is a misnomer. Anything made of acrylic is a polymer, not glass. The term “acrylic glass” became popular with marketers when extruders of high-quality acrylic plastic accomplished a clarity (transmissivity) as clear as glass. Acrylic could then be substituted for glass in applications like museum picture frames, displays, signage, etc. However, acrylic is a lightweight material, meaning it absorbs less sound than denser materials like laminated glass.

Laminated Glass

Laminated glass is specially engineered. It’s made of two layers of glass held together by a PVB interlayer, which gives it special acoustical characteristics. The soft PVB interlayer dissipates sound pressure and vibration. Think of the analogy of placing your finger on a ringing bell. The bell stops vibrating and stops making sound. Another characteristic of 1/4″ thick laminated glass is that its mass per square foot is more than twice that of same-thickness acrylic, helping it abate much more sound. It’s also used as safety glass for stores, vehicles, and other places.

If Laminated Glass Is Better, Why Do Companies Offer Acrylic Window Inserts?

Acrylic window inserts are much easier to manufacture, often costs less than laminated glass, and costs less to ship.

We offer acrylic as a lower-cost alternative to laminated glass. Although it doesn’t work as well (we refer to it as “economy grade”), there are many situations where the noise source is mostly upper-mid to upper pitch (frequency), where acrylic can perform well.

How Sun and Sound Windows Compare to Indow Windows

Indow Windows

• DIY focus. You measure and install.
• Compression frame that varies its compressions as the wall shape varies

Sun and Sound Windows:

• Full-service. We do everything.
  • Onsite assessment
  • Measuring
  • Manufacturing
  • Installation
• Baffle frame that seals to the surface and causes sound waves to make four 90-degree turns to bypass the frame.

To get a cost estimate for laminated glass soundproof window inserts for your home or office: submit our online form or Contact us.