What is a Soundproof Wall?

Understanding Basic Sound Wall Systems to Trandar Hitech Wall Solutions for Every Space

: A soundproof wall is designed to reduce sound transmission between two spaces based on the principles of mass, decoupling, and sealing. The performance of a soundproof wall is measured by STC (Sound Transmission Class). The higher the value, the better the sound insulation. However, STC is a rating for the entire wall system, not a property of any single material. An example of a prefabricated sound wall system in Thailand is Trandar Hitech Wall under the TSIS (Trandar Sound Insulation System), which ranges from STC 43 to STC 77. Different application areas, such as bedrooms, meeting rooms, hotels, or studios, require different STC ratings and system designs.

What is a Soundproof Wall? The Basics

Before diving into specialized solutions, let's understand "soundproof walls" simply.

A soundproof wall (Soundproof Wall / Sound Insulation Wall) is a wall designed to reduce the amount of sound traveling from one side to the other, whether it is speech, music, machinery noise, or impact sound. There are 3 main working principles:

1. Add Mass — Materials with higher weight and density reflect sound waves better than thin, lightweight materials.

2. Decoupling — Designing walls with air gaps or separated framing helps break the transmission path of structure-borne sound.

3. Sealing — Sound can pass through small gaps much more easily than expected, making joints, wall edges, electrical outlets, and conduit penetrations critical areas that require thorough sealing.

A common misconception is choosing a single "soundproofing material" and expecting systemic results. In reality, Sound Transmission Class (STC) is a result of the entire wall system—from surface boards, framing, and internal insulation to joint sealing—rather than the property of any single material alone.

What is Trandar Hitech Wall?

Trandar Hitech Wall is a prefabricated acoustic wall system from Trandar Acoustics designed to provide soundproofing, fire resistance, thermal insulation, and moisture resistance all in a single system, eliminating the need for conventional drywall gypsum boards.

This system integrates technology from 3 main components:

• Trandar Zoundboard — A wall board embedded with a damping compound to absorb sound vibration energy before it penetrates through.

• Heplar Pro framing — Wall framing systems designed for secure system installation and reduced structural sound transmission.

• dBphon insulation — Sound insulation placed within wall cavities to absorb sound traveling through internal air gaps.

When all 3 components are assembled under the TSIS (Trandar Sound Insulation System), you get a soundproof wall with STC ratings ranging from 43 to 77, covering all application requirements from general privacy to studio-grade acoustic performance.

Which areas are suitable for each TSIS system (classified by application)

The key rule in selecting the right acoustic wall is to start from the space requirements rather than always choosing the highest STC rating, because each space has different noise issues and performance expectations. Below is a guide classified by space usage characteristics.

• Residential and General Spaces

General Room, Bedroom, Library The main objective is privacy and undisturbed relaxation from adjacent rooms. An STC 45-50 rating is usually sufficient to make normal conversations from adjacent rooms barely audible. For libraries where quietness is prioritized for concentration, interior sound-absorbing panels can be additionally integrated to reduce reverberation within the room.

• Meeting and Working Area Group

Meeting Room, Office, Classroom, Multipurpose Room The main objective is to prevent meeting content or work discussions from leaking outside the room. The appropriate STC rating depends on information sensitivity. General team meeting rooms are typically around STC 40-45, while executive rooms or confidential data rooms should consider STC 50-55 and above. For classrooms and multipurpose rooms requiring both privacy and clear speech intelligibility, interior sound absorption should be considered alongside soundproofing walls rather than soundproofing alone.

• Comprehensive Systems Area Group

Hotel Hotels are the most complex spaces because guest privacy does not rely solely on guestroom walls. The entire system must be considered, including walls, doors (which should be acoustic doors), ceilings that must extend to the actual structural slab to block sound paths from above, as well as critical risk points like electrical outlets or utility service channels. A TSIS system rating of STC 55-58 is typically used as a standard for hotel guestroom partitions, paired with Trandar Hitech Ceiling to block sound transmission above the ceiling plenum.

• Two-Way Sound Control Area Group

Home Theater, Studio, Music Room These areas require two-way sound insulation: preventing external noise from interfering with viewing/recording, and preventing bass or loud sounds from inside from leaking out to disturb neighboring areas. Low-frequency sounds (bass) penetrate walls much more easily than high-frequency sounds, even if the wall has a high STC rating. Therefore, these areas usually require the highest level of the TSIS system. For example, in an actual studio project, the TSIS77 d215 system was used, offering up to 77 dB of sound insulation with a wall thickness of only 215 mm.

• Large-Scale Structure and Impact Noise Areas

Auditorium, Gymnasium / Indoor Stadium These spaces often face issues with both indoor reverberation and structure-borne sound, such as footsteps or balls bouncing on the floor. Choosing a sound-insulating wall system therefore requires special consideration of decoupling, combined with sound-absorbing panels to control indoor echo.

• Industrial and Machinery Areas

Engine Room Engine rooms involve both continuous loud noise and high heat. Choosing a wall system requires looking beyond just the STC value. A key highlight of Trandar Hitech Wall that addresses this well is its fire-resistant, heat-resistant, and moisture-resistant properties within a single system, with STC levels typically falling in the higher range of the TSIS system to control machinery noise from disturbing nearby areas.

There is no single soundproof wall model that is "best" for every space, as each has different objectives—ranging from bedroom privacy to bass control in a home theater. Trandar Hitech Wall, with its TSIS system covering STC ratings from 43 to 77, is designed to match the specific needs of each space rather than simply choosing the highest rating.

If you are still unsure which system your space needs, chat with the Trandar Acoustics team and share the details of your room. Our team is happy to help analyze and recommend the most suitable system specifically tailored to your needs.