What Is a Floating Floor in Anechoic Chambers? — Structure-Borne Noise Isolation Through Advanced Floor Design —

Introduction: Why the Floor Matters in Acoustic Testing

In designing anechoic chambers, the floor structure is often overlooked.
However, structure-borne noise, especially at low frequencies, tends to transmit more easily through floors than through walls or ceilings.
This makes floor-borne vibration one of the most critical noise sources affecting high-precision acoustic measurements—particularly in low-frequency and vibration-sensitive applications.

What Is a Floating Floor?

A floating floor is a structural system that physically decouples the test floor from the building foundation, preventing the transmission of vibrations and noise.
Typical configurations include:

• Base slab (concrete foundation)
• Vibration isolation layers (rubber mounts, springs, or panel supports)
• Secondary floor (walkable finish layer)

This multilayer design significantly reduces the influence of external vibration sources such as elevators, road traffic, or equipment on other building levels.

When Is a Floating Floor Necessary?

Floating floors are highly effective in the following scenarios:

• Installation in steel-frame or multi-story buildings
• Facilities located near high-traffic roads or railways
• Acoustic testing involving low-frequency bands (20–200 Hz)
• Use of high-sensitivity microphones or micro-sound detection systems
• Shared buildings housing industrial equipment or medical devices

Sonora’s Floating Floor Design: Engineering Meets Acoustics

We apply precise engineering strategies in designing floating floors for our anechoic chambers:

• Low-frequency isolation using rubber damping and multi-layer plywood panels
• Optimized support pitch based on anticipated equipment and test body loads
• Ventilation and condensation control within the underfloor cavity
• Optional integration of floor-mounted absorbers for fully anechoic floors
• Support for anchor bolt placements and cable trenches to accommodate equipment installation

Applications in MFAC and VSAC Projects

• In MFACs (Modular Fully Anechoic Chambers), floating floors enable both floor absorption and vibration isolation where required
• In VSACs (Vehicle SACs), partial floating floor systems with load-bearing capability support AVAS and vibration testing for full-size vehicles
• In medical and sensor testing chambers, floating floors are often essential for high-rise installations

Conclusion: Isolate the Vibration, Secure the Accuracy

A truly anechoic space must suppress not only airborne sound but also vibration noise.
A floating floor acts as an invisible foundation for measurement reliability, cutting off hidden vibration pathways that could contaminate test results.
Proper floor design is therefore critical—and must be tailored to the site conditions, structural environment, and measurement needs.