Soundproofing in Partition Walls: Understanding dB Ratings

What the Rw rating measures

The weighted sound reduction index Rw describes how many decibels a partition reduces airborne sound between two rooms, measured under lab or field conditions. The higher the Rw value, the better the insulation. The rating always applies to the whole assembly including connections, not just the glass or panel alone.

In practice, a system's rated Rw value from a datasheet assumes correct installation. Leaky connections at floor, ceiling or wall, open cable penetrations, or a door that does not seal well will noticeably lower the effective value on site.

Sound insulation is not sound absorption

These two terms are often confused but describe different things. Sound insulation (Rw rating) describes how much sound a wall stops from passing into the next room, protecting against noise from outside. Sound absorption describes how much sound within the same room is absorbed by a surface instead of reflected, reducing reverberation in that room.

For a meeting room where confidential conversations should not reach the adjacent office, sound insulation (the wall's Rw rating) matters most. For an open-plan office that feels loud and echoey, surface absorption also matters, for example through acoustic panels.

Realistic values at a glance

Single-glazed glass partitions (toughened safety glass, 8 to 10 mm) typically reach 32 to 36 dB. That is often sufficient for normal office conversation, though it does not reliably protect confidential content.

Double-glazed systems with an air gap between two panes reach 40 to 45 dB and suit meeting rooms with higher discretion needs. Enclosed, opaque demountable partitions with mineral wool core insulation range from 35 to 49 dB depending on thickness and construction, covering the widest range from basic room division to near solid-wall performance.

What a 10 dB difference means in practice

The decibel scale is logarithmic, not linear. A 10 dB increase corresponds roughly to a halving of perceived loudness to the human ear. The gap between a 32 dB wall and a 42 dB wall therefore feels much larger than the numbers alone suggest.

This is why the extra cost of a double-glazed system or an enclosed acoustic wall in sensitive areas is often worthwhile: the perceived gain in discretion outweighs the price difference.

Typical requirements by room use

For a meeting room used for contract negotiations or HR conversations, we recommend at least 40 dB, ideally 42 to 45 dB. The same applies to medical practices or therapy rooms for discretion reasons, where tight sealing at floor and ceiling connections matters just as much.

For an HR office handling salary and personnel discussions, an Rw rating of 40 dB or more is likewise advisable. For open office zones without confidential conversations, a single-glazed solution combined with acoustic treatment at the ceiling is often enough.

How we determine the right value

During consultation we ask specifically about room use: Do confidential conversations happen there? Does the room border a noisy zone? What is the ceiling construction? From these answers we recommend a system and state the expected Rw rating in the quote.