Secondary Glazing Under London Flight Paths: Heathrow, City Airport & Gatwick
London is served by six airports. Three of them — Heathrow, London City, and Gatwick — have approach and departure paths that pass directly over dense residential areas. Heathrow alone handles 1,300 flights daily, with aircraft passing over West London every 90 seconds during peak operations. For the estimated 725,000 Londoners living under significant flight paths, aircraft noise is the defining challenge of their homes. This guide explains how our acoustic secondary glazing is specifically engineered to defeat aircraft noise.
London's Flight Path Map: Who's Affected
Airport Noise Impact by Borough
| Airport | Most Affected Areas | Flights/Day | Altitude Over Homes | Ground dB |
|---|---|---|---|---|
| Heathrow (East Approach) | Richmond, Ealing, Hammersmith, Chiswick | ~650 | 1,000-3,000ft | 62-72dB |
| Heathrow (West Departure) | Hounslow, Feltham, Bedfont | ~650 | 500-2,000ft | 68-78dB |
| London City Airport | Tower Hamlets, Greenwich, Newham | ~220 | 300-1,500ft | 65-75dB |
| Gatwick (North Approach) | Croydon, Sutton, Merton (partial) | ~750 | 3,000-6,000ft | 55-65dB |
The Acoustic Science of Aircraft Noise
Aircraft noise has a distinctive frequency signature that differs significantly from road or rail noise. Understanding this is key to effective treatment:
- Jet engine noise: Concentrated in the 500Hz-2kHz mid-frequency range. This is the "roar" you hear during overflight. Standard glass provides reasonable attenuation here, but our 10.8mm acoustic laminate provides 45-50dB.
- Aerodynamic noise: Generated by air flowing over the fuselage and wings. Broadband noise spanning 200Hz-8kHz. More prominent during landing approach.
- Reverse thrust noise: Short-duration high-intensity bursts during landing. Reaches 80dB+ at the airport boundary. Primarily affects properties within 2km of the runway.
The critical difference from traffic noise: aircraft noise arrives from above at a steep angle. This means roof and upper-floor windows are the primary transmission path. Our surveys identify exactly which windows face the approach path and prioritise those for treatment.
10.8mm Acoustic Glass vs Aircraft Noise
| Glass Type | Low Freq (Engine Rumble) | Mid Freq (Jet Roar) | High Freq (Aerodynamic) | Overall vs Aircraft |
|---|---|---|---|---|
| Standard Double Glazing | 18-22dB | 26-30dB | 30-34dB | 26-30dB |
| 6.4mm Laminate | 24-28dB | 30-35dB | 34-38dB | 32-36dB |
| 10.8mm Acoustic Laminate ★ | 36-42dB | 44-50dB | 46-54dB | 42-54dB |
★ With 100-200mm air gap. Aircraft noise is mid-frequency dominant — our PVB interlayer is optimised for this range.
Heathrow Flight Path: Area-by-Area Analysis
Richmond & Kew
Richmond sits directly under Heathrow's eastern approach at approximately 2,000-3,000ft altitude. Aircraft noise averages 62-68dB during operations (typically 6am-11pm). The borough's extensive conservation areas and listed buildings make secondary glazing the only viable noise reduction option — replacement windows would be refused planning permission.
We've completed over 150 installations in Richmond, typically achieving 42-48dB reduction. Many clients report that after installation, they genuinely forget they live under a flight path.
Ealing & Acton
Ealing is more severely affected because aircraft are lower (1,000-2,000ft) on final approach. Combined with A40 and Great Western Main Line noise, Ealing homes face a triple acoustic challenge. Our installations here use maximum-specification 10.8mm laminate with 200mm air gaps where reveals allow.
Hammersmith & Chiswick
Hammersmith faces both the Heathrow approach path and the A4 Flyover noise. We frequently install secondary glazing that addresses both sources simultaneously — the acoustic laminate's broad-spectrum performance handles the different frequency profiles of aircraft (mid-frequency) and road (low-frequency) noise effectively.
London City Airport: Steep Approach, Intense Noise
London City Airport's unique steep approach (5.5° vs 3° standard) means aircraft pass over Tower Hamlets and Greenwich at very low altitude. Individual overflights register 65-75dB at ground level — louder than Heathrow for the closest properties.
However, LCY operates fewer flights and has a curfew (no flights on Saturday afternoons or Sundays). Our approach for LCY-affected properties focuses on upper-floor windows facing east (the approach direction), achieving 44-52dB reduction.
What 42-54dB Reduction Means Under a Flight Path
Heathrow Approach, Richmond TW9
Before: 68dB every 90 seconds, 6am-11pm
After: 24dB between flights, 32dB during overflight
An A380 landing sounds like a cat purring in another room. Between flights: complete silence.
Heathrow Approach, Ealing W5
Before: 72dB every 90 seconds (lower altitude)
After: 22dB between flights, 30dB during overflight
"We forgot we live under the flight path" — actual client feedback after 10-window installation.
City Airport, Isle of Dogs E14
Before: 70dB steep-approach aircraft every 3 minutes
After: 24dB — 46dB reduction
Business jets on LCY's steep descent produce an intense but brief noise burst. After glazing: completely inaudible inside the flat.
Gatwick Approach, Croydon
Before: 60dB aircraft at higher altitude
After: 20dB — 40dB reduction
Gatwick approaches at greater altitude are less intense. Our standard specification achieves complete silence.
Noise Insulation Grants: Do You Qualify?
Heathrow Airport Ltd operates a noise insulation programme for properties within specific noise contours. Qualifying properties may receive funding toward acoustic treatment. Contact us for a free assessment of your eligibility — we can determine whether your property falls within the scheme boundaries and help with the application process.
Even if you don't qualify for a grant, the ROI of secondary glazing under a flight path is compelling. Use our ROI Calculator to see the combined benefit of noise reduction, thermal improvement, and property value enhancement.
Installation Considerations for Flight Path Properties
Aircraft noise has unique characteristics that affect our installation approach:
- Upper floors first: Unlike traffic noise (ground level), aircraft noise primarily enters through upper-storey and roof-facing windows. We prioritise bedrooms and top-floor rooms.
- All-window treatment: Aircraft noise arrives from a wide angle. Unlike a single noise source (road, railway), flight path noise penetrates from multiple directions. We typically recommend treating all windows on affected floors.
- Seal integrity is critical: Even small gaps in acoustic seals allow mid-frequency aircraft noise to bypass the glazing. Our twin compression seal system maintains airtight contact around the full perimeter.
- Ventilation planning: Under flight paths, you can't simply "open a window" for fresh air during overflights. We can advise on trickle ventilation options that maintain acoustic performance.
Frequently Asked Questions
Which London areas are worst affected by Heathrow flight path noise?
The eastern approach to Heathrow passes over Richmond, Ealing, Hounslow, Hammersmith, and Chiswick at 1,000-3,000ft altitude. During westerly operations (70% of the time), planes arrive every 90 seconds. Western approaches affect Windsor and Slough but have less London residential impact.
Can secondary glazing block aircraft noise effectively?
Yes. Our 10.8mm acoustic laminate glass is specifically tuned for the mid-frequency range (500Hz-2kHz) where aircraft engine noise is concentrated. With a 150-200mm air gap, we achieve 42-54dB reduction — making overflights from barely noticeable to completely inaudible.
How does City Airport noise differ from Heathrow?
London City Airport uses a steep 5.5° approach (vs 3° standard) which means aircraft are lower and louder over nearby areas. However, LCY handles fewer flights (80,000/year vs Heathrow's 480,000). The noise profile is mid-frequency dominant and responds very well to acoustic secondary glazing.
Is secondary glazing better than triple glazing for aircraft noise?
Yes. Triple glazing achieves 35-40dB reduction. Secondary glazing with 10.8mm acoustic laminate achieves 42-54dB. The wider air cavity (100-200mm vs 16mm) is critical for attenuating the mid-frequency aircraft noise spectrum.
Does Heathrow's third runway affect noise levels?
The planned third runway and expanded operations will increase flight frequency. Properties already under the flight path should invest in acoustic treatment now. Secondary glazing provides protection against both current and future increased air traffic.
How much does secondary glazing cost under a flight path?
Costs range from £380-650 per window. A 3-bedroom house under the Heathrow approach typically costs £3,500-£5,500 for full treatment. Some boroughs offer noise insulation grants — we can advise on eligibility.
Can I get a grant for soundproofing under the Heathrow flight path?
Heathrow Airport runs noise insulation schemes for properties within defined noise contours. Eligibility depends on your location relative to the flight path. We work with grant recipients and can advise on how secondary glazing qualifies under these schemes.
Does secondary glazing block the vibration from low-flying aircraft?
Secondary glazing blocks the airborne noise component of aircraft (which is the dominant issue). The pressure wave vibration felt during very low overflights is less common and typically only affects properties within 500m of the runway threshold.
Silence the Skies Above Your Home
Free acoustic survey for any property under a London flight path.