Do new windows reduce noise? How much, and which glass to specify

Standard A-rated double glazing: around 30 dB reduction. Adequate for most residential streets in Leicester.

Acoustic double glazing (asymmetric panes, e.g. 6mm + 4mm): 35–38 dB reduction. Recommended for properties on A-roads, near schools, or with road noise complaints.

Acoustic triple glazing: 40–45 dB reduction. Worth specifying near the inner ring road, Welford Road or Narborough Road.

A standard sealed unit has two identical panes (e.g. 4mm + 4mm). Identical panes resonate at the same frequency and let some sound through.

Acoustic units use different pane thicknesses (e.g. 6mm + 4mm). The two panes vibrate at different frequencies, cancelling more of the sound wave. The cost difference is around £40–£70 per window.

For maximum noise reduction, specify a laminated inner pane. Laminated glass has a PVB layer that damps vibration and adds 4–6 dB of additional reduction.

Bonus: laminated glass is also much harder to break, so the security improvement comes free.

Noise coming through the walls themselves (a separate party-wall problem).

Noise coming through trickle vents (specify acoustic trickle vents, or omit if your home meets ventilation requirements elsewhere).

Letterbox-borne noise on front doors — fit a brush-sealed acoustic letterbox.