London Specialists · 10.8mm Acoustic Laminate Glass
Acoustic Window Inserts in London
Slim, internally fitted acoustic panes that sit 100–150mm behind your existing window — the quietest, least-invasive way to cut London traffic, rail and aircraft noise without replacing a single original sash.
What are acoustic window inserts?
Acoustic Window Inserts is the North-American term for what UK installers call acoustic secondary glazing — a slim secondary pane installed on the internal reveal of your existing window, 100–150mm behind the primary glass. The wide air cavity and the acoustic-laminate pane together break the sound transmission path that single-pane sash windows and even modern A-rated double glazing cannot.
We specify 10.8mm acoustic laminate glass with a Stadip Silence PVB interlayer, EPDM acoustic seals, and a 100–150mm cavity. Measured in our own London installations this combination delivers up to 54dB reduction — roughly an 80% perceived drop in road, rail, and aircraft noise.
Because the original window is untouched, the system is fully reversible and approved by conservation officers across Kensington, Chelsea, Westminster, and every other London borough we work in.
Measured performance vs. alternatives
16–20mm sealed cavity is too narrow to break low-frequency traffic noise.
10.8mm acoustic laminate + 100–150mm air gap + EPDM perimeter seals.
Costs 3–4× more, requires planning consent, and is rarely permitted on period or listed properties.
Independent dB measurements taken before and after install using a calibrated Class-1 sound-level meter. See our London case studies for room-by-room data.
When acoustic window inserts are the right call
Period sash windows you cannot replace (listed or conservation area)
Flats above busy A-roads, night-bus routes, or Tube vent shafts
Heathrow / City Airport flight paths in Richmond, Barnes, Fulham, Putney
Overground / Crossrail line-side homes in Camden, Hackney, Ealing
Restaurant or pub neighbour noise in Soho, Shoreditch, Camden
Cold draughty windows where double glazing is out of budget
Acoustic Window Inserts: FAQs
What are acoustic window inserts and how are they different from secondary glazing?
They are the same product. "Acoustic window inserts" is the North-American term; in the UK we call them acoustic or secondary glazing. We install a 10.8mm acoustic laminate pane in a slim aluminium frame on the internal reveal of your existing window, with a 100–150mm air cavity and EPDM perimeter seals.
How much noise do acoustic window inserts block in a London flat?
Independently measured installs in Kensington, Chelsea and Westminster show 45–54dB reduction with the 10.8mm Stadip Silence specification. That is enough to drop a busy A-road (around 75dB inside an unprotected room) to 21–25dB — quieter than a whispered conversation.
Are acoustic window inserts removable?
Yes. Every unit we install is fully reversible — frames are fixed to the internal reveal only, never to the original window. This is why conservation officers approve them on Grade I and Grade II listed buildings across central London.
How much do acoustic window inserts cost in London?
Indicative pricing starts at around £650 per window for standard sashes and rises with bay configurations, curved heads and large casements. Most London flats fall between £3,500 and £8,500 for a full installation. See our pricing page for transparent 2026 rates.
Will acoustic window inserts cause condensation on my original sash?
No, provided the inserts are correctly vented. We trickle-vent every frame to allow controlled moisture exchange, which keeps the original sash dry and protects the historic timber.
Do you install acoustic window inserts outside central London?
We cover every London borough including Camden, Hammersmith, Islington, Wandsworth, Richmond, Ealing, Greenwich and the City. Flight-path postcodes near Heathrow and City Airport are some of our highest-volume areas.
Free survey across London
Book a 30-minute on-site noise survey. We measure the dB intrusion at your windows, model the predicted reduction with 10.8mm acoustic laminate, and quote within 48 hours.
Request your free London surveyKeep reading
Deepen your research with our specialist resources — each link goes to a single, focused article so you can compare specifications, benefits and pricing in detail.
- 10.8mm acoustic laminate glass: full London specification
The exact glass build, interlayer and cavity depth we install for 54dB performance.
- Residential secondary glazing for London period homes
Our flagship installation service for sash and casement windows across the capital.
- Heritage & Grade II listed building secondary glazing
100% conservation-officer approval record with reversible, internally fitted units.
- Secondary glazing vs. double glazing for noise reduction
Why a 100–150mm cavity beats a 16–20mm sealed unit on traffic and aircraft noise.
- Secondary glazing prices in London (transparent 2026 rates)
Per-window and whole-flat indicative costs by glass spec and frame type.
- Free London acoustic sound survey
On-site dB measurement and a predicted-reduction model before you commit.