Introduction
Thermafl eece is a leading brand of natural thermal insulation known for its thermal efficiency and ability to improve indoor air quality. It also offers excellent acoustic properties, significantly reducing sound transmission in structures, aligning with UK Building Regulations.

Acoustic Properties
Thermafl eece enhances sound insulation in timber-framed walls or floors. Tests indicate that using Thermafl eece in a 100mm cavity can improve the sound reduction index by approximately 8dB, perceived as nearly halving the original sound level.

Sound Transmission and Reverberation
Sound hitting a wall or floor surface is partly reflected and partly transmitted to adjacent spaces. Managing sound transmission is crucial for a pleasant indoor environment. Thermafl eece also helps reduce reverberation within rooms, creating a comfortable acoustic atmosphere and improving speech intelligibility.

Testing and Standards
Thermafl eece has been tested according to ISO 354:1985 / BS EN 20354:1993, demonstrating excellent acoustic absorption, especially in the frequency range of human speech.

Acoustic Regulations
Since the 2003 revision of Part E of the UK Building Regulations, acoustic considerations have become more critical. The regulations require sound resistance between buildings, applicable to various settings, including schools and residential rooms. Using absorbent materials like Thermafl eece in wall voids contributes to meeting these acoustic standards.

Sound Insulation of Stud Walls
Stud wall construction with Thermafl eece involves 100mm x 50mm timber studs at 600mm centers, with 15mm plasterboard on each side and 100mm Thermafl eece in the cavity. Measurements of airborne sound insulation were conducted according to BS EN ISO 140: Part 3 (1995) by BRE, accredited for sound insulation measurement.