Updated September 18, 2025
Noise is one of the most common—and frustrating—challenges during construction projects. Whether the work is happening in a hospital, airport, office building, or university, excess noise disrupts occupants, impacts productivity, and even raises safety concerns. That’s why understanding ASTM E90, the test used to measure sound transmission in wall systems, is critical for Project Managers, Facilities Managers, and contractors.
What Is ASTM E90?
ASTM E90 is the Standard Test Method for Laboratory Measurement of Airborne Sound Transmission Loss of Building Partitions and Elements. In simple terms, it measures how well a wall assembly blocks sound from passing through.
How it works: a test specimen is mounted between two calibrated rooms, broadband sound is emitted in the source room, and microphones record levels in both rooms. The measured transmission loss across frequencies is then converted to a single-number rating called the Sound Transmission Class (STC).
The higher the STC rating, the better the wall is at reducing sound transmission.
What Is a Good STC Rating?
For context:
- A typical interior partition with one layer of 1/2-inch gypsum on each side of wood studs has an STC rating around 33.
- Insulated or double-layer stud walls can reach the mid-40s to 50+, depending on construction.
- A standard single-pane window is typically STC 26–28.
- At STC 40, loud speech is reduced to a muffled murmur on the receiving side.
In sensitive environments like hospitals, where patient comfort and HIPAA privacy are essential, or in office buildings where productivity is at stake, higher STC values make a measurable difference.
RealWall and FireblockWall: Sound Attenuation in Action
STARC Systems has tested its temporary wall systems using ASTM E90:
- RealWall™: independently tested to reduce renovation noise by up to 50%, delivering quieter, more professional-looking spaces during even the most disruptive projects.
- FireblockWall™: laboratory tested with an STC rating of 40, making it an excellent choice for healthcare renovations and other occupied environments where fire safety and moderate noise reduction are both required.
Unlike drywall or plastic sheeting, both systems are reusable across multiple projects, saving money while delivering sound performance and compliance.
Why Sound Attenuation Matters in Construction
Sound attenuation isn’t just a comfort feature; it’s often a compliance and safety issue. Consider these scenarios:
- Hospitals: Noise reduction supports patient healing, protects privacy, and prevents disruptions to care teams.
- Airports: Sound attenuation keeps operations moving while construction happens in terminals.
- Corporate Offices: Reducing noise allows employees to remain productive during renovations.
By choosing wall systems with proven STC ratings, Project Managers can reduce disruptions, improve outcomes, and deliver more successful projects.
FAQs About ASTM E90 and Sound Transmission
ASTM E90 measures how well a wall system blocks airborne sound by determining its Sound Transmission Class (STC) rating.
👉 In short: ASTM E90 measures a wall’s ability to block airborne sound.
An STC rating of 40–50 provides effective noise reduction for most commercial and healthcare projects. Higher ratings indicate stronger sound performance.
👉 In short: STC 40–50 is strong enough for most occupied construction projects.
It minimizes disruptions, protects privacy, and improves safety in occupied environments like hospitals, offices, and airports.
👉 In short: Sound attenuation reduces noise disruptions and improves safety in occupied spaces.
Drywall is disposable and less efficient. STARC’s FireblockWall (STC 40) and RealWall (up to 50% reduction) are reusable, faster to install, and more cost-effective long term.
👉 In short: STARC’s RealWall and FireblockWall provide industry-leading noise reduction while delivering better ROI than drywall.
Takeaways: Block Construction Noise with STARC
For Project Managers, Facilities Managers, and contractors, ASTM E90 provides a clear way to evaluate sound attenuation. With STC-tested wall systems like FireblockWall™ and RealWall™, you can deliver projects that protect occupants, reduce disruptions, and improve long-term ROI.
Ready to explore STARC’s solutions? Talk to our team.