Acoustic Glazing Solutions

Specifier-grade sound insulation for London properties

Our acoustic glazing solutions provide exceptional sound insulation, creating a quieter and more peaceful indoor environment. Perfect for properties near busy roads, flight paths, or in urban areas with high noise pollution.

Stairway window with secondary glazing installation showcasing acoustic insulation properties

How Acoustic Glazing Works

Diagram showing acoustic secondary glazing layers and sound wave reduction

Acoustic secondary glazing creates an additional barrier against sound, with the air gap between your existing window and the secondary glazing significantly reducing noise transmission. Different glass thicknesses and laminated acoustic glass options further enhance sound reduction performance.

Up to 80% noise reduction (45-50dB)
Wide range of acoustic glass options
Customizable air gap dimensions
Perfect for listed buildings where replacement windows aren't allowed

Benefits of Acoustic Glazing

Before and after comparison of acoustic secondary glazing installation showing noise reduction benefits

Enhanced Comfort: Reduce external noise intrusion for a more peaceful living or working environment
Improved Sleep Quality: Minimize nighttime disturbances from traffic or urban noise
Increased Concentration: Create quieter spaces better suited for work, study, or relaxation
Added Thermal Insulation: Additional window layer also improves energy efficiency
Preserves Original Windows: Ideal solution for listed buildings and conservation areas

Acoustic performance specification

Acoustic performance is governed by three specifiable variables: the mass and damping of the secondary pane, the depth of the isolating cavity, and the airtightness of the perimeter seal. Weighted sound reduction index (Rw, measured to BS EN ISO 10140) rises as each is optimised, but traffic and rail noise are dominated by low-frequency energy, so the C_tr spectrum adaptation term is the figure that matters on a London arterial route. A unit quoted at Rw 45dB with C_tr −7 delivers roughly 38dB against bus and HGV rumble.

Typical acoustic secondary glazing configurations and performance
Glass specification	Cavity	Indicative Rw	Best suited to
4mm float	50–70mm	32–35dB	Quiet side roads, thermal-led projects
6.4mm laminated	100mm	38–41dB	Residential streets with steady traffic
8.8mm acoustic laminate	100mm	42–46dB	Bus routes, high streets, night-time noise
10.8mm Stadip Silence	100–150mm	48–54dB	Arterial roads, rail corridors, flight paths

Design targets and standards

BS 8233:2014 sets internal ambient noise guidance of 35dB L_Aeq,16hr in living rooms and 30dB L_Aeq,8hr in bedrooms, with 45dB L_Amax for individual night-time events. Working back from a measured façade level gives the required façade sound reduction: a 70dB free-field level outside a bedroom needs roughly 40dB of glazing performance once the 3dB façade correction is applied. Where a planning condition cites these targets, we issue calculated performance figures for each opening rather than a single headline number.

Detailing that protects the numbers

Perimeter sealing: a 1% unsealed gap can cost 10dB, so frames are bedded to the reveal with a continuous compressible seal.
Asymmetric panes: pairing dissimilar glass thicknesses avoids coincidence dip alignment between the primary and secondary pane.
Cavity linings: acoustically absorbent reveal linings suppress cavity resonance in deep Georgian and Victorian reveals.
Trickle ventilation: acoustic-attenuated vents maintain Part F background ventilation without short-circuiting the acoustic seal.

Because the original window is untouched, this specification route remains available in listed buildings and conservation areas where replacement double glazing would be refused.

Learn More: Secondary Glazing Noise Reduction

Want to understand how secondary glazing can cut outside noise by up to 80%? Discover detailed acoustic glass options, air gap strategies, and solutions for listed buildings on our dedicated page.

Explore Secondary Glazing Noise Reduction