London Specialists · 10.8mm Acoustic Laminate Glass
Sound Isolation Windows in London
The UK's most effective sound isolation system for existing windows. A 10.8mm acoustic laminate pane, a deep 100–150mm air gap and EPDM perimeter seals together break the low-frequency transmission path that double glazing leaves wide open.
What are sound isolation windows?
Sound Isolation Windows 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 sound isolation windows 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
Sound Isolation Windows: FAQs
What is the difference between sound isolation windows and soundproof windows?
They describe the same goal — reducing sound transmission through the window aperture. True "soundproofing" (100% blocking) is physically impossible; what we deliver is sound isolation of up to 54dB, equivalent to an 80% perceived reduction in road, rail and aircraft noise.
Why are sound isolation windows more effective than triple glazing?
Triple glazing relies on three closely spaced panes (16–20mm gaps). Low-frequency noise — bass from buses, trains and aircraft — passes through that narrow cavity almost unimpeded. Our system places the secondary pane 100–150mm behind the primary glass; that wide cavity is the single biggest acoustic variable and the reason we achieve up to 54dB.
Can sound isolation windows be installed on listed buildings in London?
Yes. Because the system is internal and fully reversible, it does not alter the external appearance of a Grade I or Grade II listed property. We have a 100% conservation-officer approval record across Kensington, Chelsea, Westminster, Mayfair and Belgravia.
Do sound isolation windows also improve thermal insulation?
Significantly. The same 100–150mm air cavity that blocks noise also creates a buffer against heat loss. Independent thermal modelling shows U-value improvements of 60% or more on single-glazed sash windows, with measurable reductions in heating bills.
How long does a sound isolation window installation take?
A typical 4–6 window London flat is surveyed, manufactured and installed within 4–6 weeks. The on-site fit itself takes one to two days with no scaffolding and no external mess.
What is the cost of sound isolation windows in London?
Around £650 per window for a standard sash with 10.8mm acoustic laminate, scaling with bay and casement complexity. Whole-flat projects typically land between £3,500 and £8,500 — roughly half the cost of replacement double glazing on a period property.
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.