IndowPRO Performance for Acoustic Consultants & Engineers

Engineer superior acoustic environments with the IndowPRO secondary glazing system. Achieve STC ratings up to 51 and OITC ratings up to 36 over a standard storefront window, with performance validated by accredited, third-party ASTM E90 lab testing.

Lab-Verified STC 51 & OITC 36 Performance

Solving complex acoustic challenges in existing buildings requires a systems approach that moves beyond the limitations of the primary window. IndowPRO creates a predictable, high-performance assembly by introducing a significant, decoupled air gap and optimizing the mass of acoustic-grade glazing, all within a verifiably airtight frame system (<0.01 CFM).

The IndowPRO system is a secondary glazing solution that supports customer glazing selection to meet specific project goals. The following lab-tested results demonstrate the acoustic performance of IndowPRO with various glazing types and air gaps when installed over a baseline commercial aluminum storefront window (STC 29).

Primary Window: 1/4" Tempered Glass (STC 29)

IndowPRO Glazing Insert: None (Primary Window Only)Air Gap: N/AResulting STC: 29Resulting OITC: 25*Test Report #: NOAL 25-06063
IndowPRO Glazing Insert: 5/16" Acoustic LaminatedAir Gap: 1.25"Resulting STC: 43Resulting OITC: 31Test Report #: NOAL 25-06065
IndowPRO Glazing Insert: 5/16" Acoustic LaminatedAir Gap: 4.00"Resulting STC: 51Resulting OITC: 36Test Report #: NOAL 25-06069

* OITC estimated for baseline

Secondary Glazing, Redefined

The modular frame ships disassembled to reduce logistics costs, then snaps together quickly on-site for fast, non-disruptive installation.

Solving Real-World Acoustic Challenges

  • Hospitality/Transportation Noise

    Challenge:

    Mitigate street noise to meet premium brand standards.

    Solution:

    IndowPRO with 4" air gap and laminated glass achieved STC 51, creating a serene guest environment.

  • Atrium Window Noise Damping

    Challenge:

    Damping atrium event noise from reaching guest rooms

    Solution:

    IndowPRO with Acoustic Laminated Glass in mullion array.

Let's Solve Your Window Challenge

Your Complete Technical & Specification Library

Access the documentation needed to model, specify, and present the IndowPRO system.

Project Support

Our team is available to aid your analysis and planning. We can discuss glazing options and partner with you to engineer a solution that meets your client's performance goals.

About IndowPRO Installation Architectural Details Performance