FENSA-registered glazing experts. Made-to-measure sealed units, shipped UK-wide, backed by a 10-year warranty.
Acoustic triple glazing — when DG isn't enough, flight-path-grade noise reduction
For most domestic noise problems, acoustic double glazing is plenty. For the rest — flight-path properties, freight-line frontage, motorway-and-rail concurrent exposure, and dwellings under planning conditions of Rw 42+ dB — triple is the answer. A three-pane, two-cavity stack with acoustic-PVB laminated outer and acoustic-PVB laminated middle delivers Rw 44 dB and up, the gold-standard residential acoustic spec. Pane Relief manufactures triple-glazed acoustic units to BS EN 12758 with lab-measured Rw + Ctr certificates on request. Frame depth and weight implications matter for triple — see the FAQ and the trade desk if you're not sure your rebate will take a 44mm overall unit.
You live near an airport, freight line, or motorway
Heathrow / Gatwick / Stansted approach corridors, mainline freight (Channel Tunnel-bound containers, night sleeper traffic), motorway frontage where DG isn't cutting it. Triple acoustic is the top-tier residential spec. Free UK delivery, 10-year edge-seal warranty, helpline 08:00-18:00 Mon-Fri for spec consultation — and a free, honest phone triage to check whether triple is actually needed vs heavy DG.
Configure acoustic triplePlanning condition Rw 42+, BS 8233 critical site
BREEAM Hea05 internal noise, residential developments inside the 57+ Lden noise contour, hospital ward and school classroom upgrades, hotel-room noise specs. Net 30 trade accounts, scheduled site delivery, BS EN ISO 10140 lab-measured Rw + C + Ctr certificates on every order, full BS EN 12758 + 1279 documentation.
Trade & specifier pricingAcoustic triple — common build configurations
Two cavities, three panes. Acoustic-PVB in the outer and middle pane delivers the dB; argon or krypton fill optimises thermal alongside.
6.4-12-4-12-4 acoustic TG
Rw ~44 dB. Entry-point triple acoustic. Acoustic-PVB outer. 38mm overall.
8.8-14-4-14-4 acoustic TG
Rw ~46 dB. Heavy acoustic outer + dual wider cavities. Flight-path or motorway frontage. 44mm overall.
10.8-12-6.4-12-4 dual-lam TG
Rw ~48 dB. Dual acoustic-PVB lam (outer + middle). Worst-case noise. 44mm overall.
Acoustic + Low-E + warm-edge TG
Rw 44 dB + U-value 0.7 W/m²K. Passive-house-grade acoustic + thermal in one unit.
Acoustic + safety TG
Outer toughened + acoustic-PVB lam middle. Critical-location compliant + Rw 44 dB. School and hospital spec.
Custom spec
Bring a noise survey or BS 8233 calc — we'll quote a triple build that hits the target Rw + Ctr.
When triple beats DG — and when it doesn't
Triple is the right answer for low-frequency-dominant noise. DG is the right answer for mid-frequency-dominant noise. Knowing your noise spectrum saves money.
Triple wins on low-frequency noise
- Aircraft jet roar — peak energy 50-500 Hz. Triple delivers a noticeable improvement over even the heaviest acoustic DG.
- Diesel truck and freight train rumble — peak 80-250 Hz. Triple is meaningfully better, especially at the bedroom-rest threshold.
- Music bass through walls — irrelevant (transmitted through structure not air), but for an open-window neighbour party triple still helps.
- Power-station / depot plant noise — broadband but with strong sub-200 Hz content. Triple recommended.
DG wins on mid-frequency noise (and price)
For pure traffic noise (cars and light vans), pedestrian noise, sirens, dog barking, school-run chatter, dawn refuse trucks — the energy is concentrated in 500 Hz - 4 kHz where acoustic-PVB DG performs almost as well as triple at half the cost and a third of the weight. Triple's advantage only widens significantly when low-frequency content is dominant. If you're not sure what your noise looks like, call the helpline: a 60-second description of the source usually pins down which option is right.
Acoustic triple glazing — common questions answered
Q: Will an acoustic triple unit fit my existing window frame?
Almost certainly no — and this is the single biggest practical difference between acoustic DG and acoustic triple. Standard UK casement and tilt-and-turn frames are built for 24-28mm rebates (DG-only). Acoustic triple units are 38-44mm overall — they need a deeper rebate, which usually means a frame replacement at the same time. The exception: some modern (post-2010) European-system frames (Schueco, Reynaers, Internorm, Velfac) accept a triple unit in the existing rebate. Send us the frame model number and we'll confirm compatibility before you order.
Q: How much heavier is acoustic triple than acoustic DG?
Roughly double per square metre. Acoustic DG (6.4-16-4) weighs around 26 kg/m². Acoustic triple (6.4-12-4-12-4) weighs around 36 kg/m². A heavy dual-lam acoustic triple (10.8-12-6.4-12-4) is around 52 kg/m². This matters for sash windows, opening casements with weak hinges, and any old frame with tired ironmongery. For a fixed picture window in a properly engineered modern frame, the weight is a non-issue. Always quote the pane weight to your fitter at order time — we flag it on every product spec sheet and the configurator output.
Q: Will acoustic triple also be the best thermal performance?
Yes — by some margin. Acoustic triple with low-E coatings on both inner cavity faces and an argon (or krypton) fill delivers U-value 0.7-0.9 W/m²K, well into Passive-House territory and approximately double the thermal performance of an A-rated double-glazed unit. If you're spec'ing acoustic triple anyway, the marginal cost of adding low-E coatings is small (~5-10%) and the return is significant — the configurator quotes "acoustic + low-E + warm-edge" as the default combo build.
Q: I'm in the 57+ Lden noise contour for Heathrow. What spec should I be specifying?
Standard local-authority planning conditions for the 57+ Lden / 60+ LAeq contours typically call up Rw 42-44 dB glazing with MVHR mechanical ventilation (no trickle vents). Heavier 60+ Lden / 63+ LAeq contours typically need Rw 46-48 dB — which is dual-laminated acoustic triple territory. Get a copy of the planning condition wording from your local authority, send it to us, and we'll spec a unit that demonstrably hits the number. Lab-measured Rw + Ctr certificate supplied as standard for planning-condition orders.
Q: Triple is famously bad for ventilation. How do I detail this?
Acoustic triple + trickle vents is self-defeating: a trickle vent typically gives 25-30 dB Dn,e,w, dragging the whole assembly down to a 30-35 dB Rw effective performance. The right answer is MVHR (mechanical ventilation with heat recovery) providing the Approved Document F ventilation rate without any openings in the wall envelope. If MVHR isn't in the build, specify acoustic trickle vents (rated 35-40 dB Dn,e,w) and accept a 3-5 dB real-world performance penalty on the glazing. We'd raise this on the helpline call if you're spec'ing acoustic triple without MVHR.
Q: Can acoustic triple be specified as toughened or laminated for safety?
Yes. The inner pane can be toughened (BS EN 12150) for critical-location door and low-window applications. The middle and outer panes are already typically laminated (BS EN 14449) for the acoustic build. Toughened + dual-acoustic-laminated is a popular spec for street-facing ground-floor city-centre dwellings combining the legal safety requirement, maximum noise attenuation, and full retention if the inner pane is impacted. Specify "acoustic triple + safety" in the configurator and we ship the right build.
Q: How much more expensive than acoustic DG?
Roughly: +80% to +120% on the glass unit alone, plus the frame replacement cost if your existing frames can't take a 38-44mm rebate. For a 1.5m² bedroom window, expect the unit cost to step from ~£280 (acoustic DG) to ~£560 (acoustic triple), plus frame work if needed. The configurator quotes the unit live; trade desk for frame-and-fit packages. Worth the spend if the noise survey says you need it — overkill otherwise.
Q: What's the lead time and warranty?
Acoustic triple (stock builds): 14-18 working days. Bespoke shaped, oversized, dual-laminated, or krypton-filled: 18-25 working days. Every triple unit ships with a 10-year edge-seal warranty (BS EN 1279-2), 5-year PVB lamination warranty, and optional BS EN ISO 10140 lab-measured Rw + C + Ctr certificate (specify at order; supplied to planning officers / Building Control). UKCA-marked, full DoP package on request.
Related guides and specifications
Flight-path-grade noise reduction — Rw 44 dB+, planning-condition spec
Call 0117 330 3057 (08:00-18:00 Mon-Fri) with your planning-condition wording or noise survey. Or send drawings for a triple-spec quote with frame compatibility check.