{"product_id":"triple-glazed-acoustic-unit-44db-rw","title":"Triple Glazed Acoustic Unit (44 dB Rw)","description":"\n\u003cp class=\"pr-flagship__lede\"\u003e\u003cstrong\u003eThe hard-spec acoustic flagship — 44 dB Rw under BS EN ISO 717-1\u003c\/strong\u003e. A triple-glazed unit built with asymmetric pane thicknesses, an acoustic-PVB laminated outer, and twin argon-filled cavities tuned to disrupt coincidence-frequency resonance. This is the unit specified by acoustic consultants for properties under flight paths, on A-road frontage, in rail-corridor housing, and against the M25.\u003c\/p\u003e\n\n\u003cp\u003eRw 44 dB is meaningful: the perceived loudness reduction from outside to inside is roughly four times — the difference between a busy A-road at 70 dB(A) sounding like background conversation, and the same road sounding like a quiet office. Combined with a frame and trickle-vent assembly compatible with acoustic performance (sealed perimeter, acoustic vents where required), this unit drives whole-window R\u003csub\u003ew\u003c\/sub\u003e performance into the 40-43 dB range — territory previously only reachable with secondary glazing.\u003c\/p\u003e\n\n\u003ch2\u003eWhy asymmetric panes — the physics\u003c\/h2\u003e\n\u003cp\u003eGlass blocks sound by mass: thicker panes block more. But every pane has a \"coincidence frequency\" — a frequency at which the acoustic wave matches a resonant flexural mode of the pane, and the pane suddenly stops blocking sound. For 4mm float, coincidence is around 3000 Hz; for 6mm it shifts to ~2000 Hz; for laminated 8.8mm it spreads across a wider band but with lower peak dip thanks to the PVB damping.\u003c\/p\u003e\n\n\u003cp\u003eAn asymmetric stack — 8.8mm acoustic-laminated outer \/ 4mm middle \/ 4mm inner — places coincidence dips at different frequencies in each pane, so a single frequency can't punch through the assembly. The acoustic PVB interlayer adds viscoelastic damping that further suppresses the laminated pane's dip. Together, these mechanisms drive R\u003csub\u003ew\u003c\/sub\u003e 5-7 dB above what a symmetric triple at the same total mass would deliver.\u003c\/p\u003e\n\n\u003ch2\u003eTechnical specification\u003c\/h2\u003e\n\u003ctable class=\"pr-spec-table\"\u003e\n  \u003ctr\u003e\n\u003cth\u003eOverall thickness\u003c\/th\u003e\n\u003ctd\u003e~42-44mm (asymmetric build)\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eBuild-up\u003c\/th\u003e\n\u003ctd\u003e8.8mm acoustic-PVB laminated outer (4+4 with 0.76mm acoustic interlayer) \/ 12mm argon \/ 4mm clear \/ 12mm argon \/ 4mm clear\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eCavities\u003c\/th\u003e\n\u003ctd\u003e2 × 12mm argon-filled (BS EN 1279-3)\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eR\u003csub\u003ew\u003c\/sub\u003e (Weighted Sound Reduction Index)\u003c\/th\u003e\n\u003ctd\u003e44 dB to BS EN ISO 717-1\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eR\u003csub\u003ew\u003c\/sub\u003e + C\u003csub\u003etr\u003c\/sub\u003e (road traffic spectrum)\u003c\/th\u003e\n\u003ctd\u003e40-41 dB (typical)\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eU-value (centre-pane, with low-E)\u003c\/th\u003e\n\u003ctd\u003e0.8 W\/m²K\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eg-value\u003c\/th\u003e\n\u003ctd\u003e0.52\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eLight transmittance\u003c\/th\u003e\n\u003ctd\u003e~70%\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eWeight\u003c\/th\u003e\n\u003ctd\u003e~38 kg\/m² — confirm frame load capacity\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003cth\u003eStandards\u003c\/th\u003e\n\u003ctd\u003eBS EN 1279, BS EN ISO 717-1 (acoustic), BS EN 14449 (laminated), BS EN 12600 (impact via laminated)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eWhere this unit is the right call\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eHeathrow, Gatwick, Manchester, Stansted, Birmingham flight-path frontage\u003c\/strong\u003e — particularly for properties inside the 57 dB L\u003csub\u003eAeq,16h\u003c\/sub\u003e noise contour where local-authority noise insulation grants may apply.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eA-road and motorway-adjacent housing\u003c\/strong\u003e — particularly retrofit projects where existing single or first-generation double glazing is delivering only R\u003csub\u003ew\u003c\/sub\u003e 25-28 dB.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eRail-corridor properties\u003c\/strong\u003e — main-line Network Rail routes, HS1, HS2, Crossrail. Train noise has a strong low-frequency component that asymmetric stacks handle better than symmetric.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eHotels, hospitals, schools, and residential care in urban centres\u003c\/strong\u003e — where building-regs Approved Document E (sound insulation) requires verified performance.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eRecording studios, home cinemas, and high-spec residential\u003c\/strong\u003e — where guaranteed noise floors drive acoustic specifications regardless of external noise.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eThe full acoustic-glazing decision tree — laminated vs asymmetric vs triple, Rw vs Rw+Ctr, and how the dB(A) reduction translates to perceived loudness — is on the \u003ca href=\"\/pages\/acoustic-glass\"\u003e\u003cstrong\u003eacoustic glass topical page\u003c\/strong\u003e\u003c\/a\u003e, with installation and frame-seal advice. For a simpler double-glazed acoustic option, see the \u003ca href=\"\/products\/specialist-acoustic-laminated-glass-asymmetric-double-glazed-unit\"\u003eSpecialist Acoustic Laminated double-glazed flagship\u003c\/a\u003e.\u003c\/p\u003e\n\n\u003ch2\u003eStock sizes and pricing\u003c\/h2\u003e\n\u003cp\u003eFive UK-standard stock sizes are below. Dispatch 14-18 working days (acoustic-PVB lamination + triple-glazed assembly is a longer process than standard triple). Custom sizes — including bespoke acoustic stacks tuned to a specific noise spectrum (e.g., low-frequency dominant rail noise) — are priced via the \u003ca href=\"\/pages\/configure\"\u003e\u003cstrong\u003econfigurator\u003c\/strong\u003e\u003c\/a\u003e with an option for a free acoustic-consultant phone consultation.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eFrame load note:\u003c\/strong\u003e at ~38 kg\/m² this is one of the heaviest mainstream IGUs available. A 1500 × 1200 unit is ~68 kg. Specify reinforced hinges and check sash-balance ratings. Aluminium and laminated-timber frames are the appropriate choices; older PVCu frames typically cannot accept this load.\u003c\/p\u003e\n\n\u003ch2\u003eCertification and standards\u003c\/h2\u003e\n\u003cp\u003eEvery unit ships with: UKCA mark, BS EN 1279 DoP, R\u003csub\u003ew\u003c\/sub\u003e test certificate from a UKAS-accredited acoustic laboratory (BS EN ISO 10140 test methodology), laminated-glass BS EN 14449 certification, and CWCT (Centre for Window \u0026amp; Cladding Technology) test pack on request. For local-authority noise-grant applications, we can supply the R\u003csub\u003ew\u003c\/sub\u003e + C\u003csub\u003etr\u003c\/sub\u003e + C figures as a pack.\u003c\/p\u003e\n\n\u003ch2\u003eFrequently asked questions\u003c\/h2\u003e\n\u003ch3\u003eWhat does R\u003csub\u003ew\u003c\/sub\u003e 44 dB actually sound like vs my current windows?\u003c\/h3\u003e\n\u003cp\u003eA typical 1990s 4-12-4 double-glazed unit achieves R\u003csub\u003ew\u003c\/sub\u003e 28-30 dB. Upgrading to R\u003csub\u003ew\u003c\/sub\u003e 44 dB is a 14-16 dB improvement — perceived as roughly a 75% loudness reduction. Heavy traffic that previously dominated the room drops to the level of background conversation. Note: this assumes a fully-sealed frame and acoustic-compatible trickle vents; air leakage paths around the unit can lose 8-10 dB.\u003c\/p\u003e\n\n\u003ch3\u003eWhat's the difference between R\u003csub\u003ew\u003c\/sub\u003e, R\u003csub\u003ew\u003c\/sub\u003e+C\u003csub\u003etr\u003c\/sub\u003e, and dB(A)?\u003c\/h3\u003e\n\u003cp\u003eR\u003csub\u003ew\u003c\/sub\u003e is a single-number weighted index across 100-3150 Hz (BS EN ISO 717-1). C\u003csub\u003etr\u003c\/sub\u003e is a correction factor weighted toward road-traffic frequencies (low-frequency-heavy). R\u003csub\u003ew\u003c\/sub\u003e+C\u003csub\u003etr\u003c\/sub\u003e is the more honest figure for road-noise scenarios. dB(A) is an A-weighted decibel level, used for measuring actual noise — not for rating glass.\u003c\/p\u003e\n\n\u003ch3\u003eIs triple acoustic actually better than the best double acoustic?\u003c\/h3\u003e\n\u003cp\u003eMarginally — typically 2-4 dB at the high end. The R\u003csub\u003ew\u003c\/sub\u003e improvement from double-to-triple is smaller than asymmetric-pane mass gains within a double. The case for triple acoustic is when you want both Rw 42+ AND U-value 0.8 — i.e., thermal and acoustic in one stack. For acoustic-only priorities, a double-glazed acoustic-laminated at lower cost is often the better choice.\u003c\/p\u003e\n\n\u003ch3\u003eWill this fit my existing frame?\u003c\/h3\u003e\n\u003cp\u003eAt 42-44mm overall, only thermally-broken aluminium and timber-aluminium composite frames with 70-90mm depth will accept it. Standard PVCu and older aluminium will need full frame replacement, not just reglazing. We strongly recommend an installer site visit before specifying — frame compatibility is the most common project blocker for acoustic triple.\u003c\/p\u003e\n\n\u003ch3\u003eDo I need acoustic trickle vents?\u003c\/h3\u003e\n\u003cp\u003eYes — Building Regs Approved Document F requires background ventilation, but standard trickle vents short-circuit the acoustic performance. Specify acoustic trickle vents (Rytons Aircore, Greenwood Acoustic, or equivalent) — typically R\u003csub\u003ew\u003c\/sub\u003e(C;C\u003csub\u003etr\u003c\/sub\u003e) ≥ 38 dB so they're not the weak link. Vent acoustic ratings are independent of glass acoustic ratings.\u003c\/p\u003e\n\n\u003ch3\u003eLocal-authority noise-grant compliance?\u003c\/h3\u003e\n\u003cp\u003eMost UK noise-mitigation grant schemes (around airports + major motorways) accept R\u003csub\u003ew\u003c\/sub\u003e ≥ 35 dB as the minimum specified glazing. R\u003csub\u003ew\u003c\/sub\u003e 44 dB exceeds this comfortably and qualifies for top-tier funding bands where applicable. We supply the test pack at no charge for grant applications.\u003c\/p\u003e\n\n\u003ch3\u003eWarranty?\u003c\/h3\u003e\n\u003cp\u003e10 years on edge-seal integrity (BS EN 1279-2). 10 years on acoustic-PVB delamination (manufacturer's BS EN 14449 standard warranty). 10 years on argon retention to ≥80% of initial fill. Acoustic R\u003csub\u003ew\u003c\/sub\u003e performance is warranted at the certified test value at installation date — declining performance is not warrantable because it's typically a frame-seal or vent issue, not a glass issue.\u003c\/p\u003e\n","brand":"Pane Relief","offers":[{"title":"600 × 400 mm","offer_id":61853203202378,"sku":"TG-AC44-600x400","price":45.0,"currency_code":"GBP","in_stock":true},{"title":"800 × 600 mm","offer_id":61853203235146,"sku":"TG-AC44-800x600","price":80.0,"currency_code":"GBP","in_stock":true},{"title":"1000 × 800 mm","offer_id":61853203267914,"sku":"TG-AC44-1000x800","price":133.0,"currency_code":"GBP","in_stock":true},{"title":"1200 × 1000 mm","offer_id":61853203300682,"sku":"TG-AC44-1200x1000","price":199.0,"currency_code":"GBP","in_stock":true},{"title":"1500 × 1200 mm","offer_id":61853203333450,"sku":"TG-AC44-1500x1200","price":299.0,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0895\/3515\/2458\/files\/triple-glazed-insulated-glass-unit-igu-cutaway_104e02f2-d2b6-4852-a4c8-e6b512bd20f3.webp?v=1779007261","url":"https:\/\/panerelief.co.uk\/products\/triple-glazed-acoustic-unit-44db-rw","provider":"Pane Relief","version":"1.0","type":"link"}