London's premier specialists for soundproof secondary glazing in listed buildings and conservation areas.
25+ Years
Experience
Fully Insured
£5M Coverage
10-Year
Guarantee
Heritage
Approved
Real results from homeowners across London's finest postcodes. Every review verified, every installation guaranteed.
"The noise reduction is remarkable -- we can finally enjoy peaceful evenings despite the busy road. Installation was completed in a single day, and our heating bills have dropped by £60 a month."
Victoria & James
75% noise reduction
"Secondary glazing was the perfect solution -- no planning permission needed, and we kept all our period features. The acoustic improvement is incredible."
Sarah T.
U-value 5.2 to 2.1
"Our landlord approved it because it's fully reversible. The condensation has completely disappeared, and we can't hear the building work anymore."
Michael & Emma
100% condensation eliminated
See how much you could save on heating bills with secondary glazing. Adjust the sliders to match your property.
Estimated Annual Saving
£700
Based on 28% reduction in heating costs
5-Year ROI
£3,500
Total savings over 5 years across 8 windows
Free survey, no obligation. Get a guaranteed quote within 24 hours.
New regulations require all rental properties to achieve a minimum EPC Band C by 2028. Non-compliance could mean fines of up to £30,000.
From 2028, all new tenancies in England and Wales must have an EPC rating of Band C or above. Existing tenancies will follow by 2030. For period properties with single-glazed sash windows, this is a significant challenge.
Secondary glazing is one of the most effective EPC improvements for heritage properties because it reduces window U-values from 5.0 to 1.8 W/m²K -- a 64% reduction in heat loss without altering the external appearance.
Improve EPC by 1-2 bands with a single upgrade
No planning permission required for most properties
Fully reversible -- protects your property investment
10.8mm acoustic glass for premium rental appeal
Typical result with 10.8mm acoustic secondary glazing
U-Value Before
5.0 W/m²K
U-Value After
1.8 W/m²K
Heat Loss Reduction
64%
Glass Spec
10.8mm
Everything you need to know about secondary glazing -- from acoustic performance and planning permission to why professionals outperform DIY every time.
Secondary glazing is a discreet, internal window system fitted behind your existing windows. Unlike replacement double glazing, it preserves your original windows entirely -- making it the preferred solution for listed buildings, conservation areas, and period properties across London.
A precision-engineered aluminium frame is fixed into your window reveal (not the original frame), holding high-performance glass at an optimal distance from the existing pane. This air cavity is what delivers the exceptional acoustic and thermal performance that secondary glazing is known for.
The key advantage over replacement windows is the air gap. Standard double glazing has a 12-16mm cavity. Secondary glazing creates a 100-150mm cavity -- up to ten times wider. This dramatically improves low-frequency sound absorption, which is why secondary glazing consistently outperforms double glazing for noise reduction.
54 dB
Maximum noise reduction
10.8mm acoustic glass
64%
Heat loss reduction
U-value 5.0 to 1.8
25+ yrs
Typical service life
With full warranty
Professional soundproof secondary glazing for listed buildings, Victorian properties, and period homes across Richmond, Hampstead, Chelsea, and all London boroughs
From Our Portfolio
A Grade II listed Victorian townhouse on a busy arterial road. The homeowner was losing sleep to constant traffic noise. We installed 10.8mm acoustic laminated secondary glazing across 12 original sash windows without altering the exterior appearance, achieving full conservation officer approval.
A period flat overlooking the Embankment with severe road and river traffic noise. We fitted slim-profile acoustic secondary glazing to twin casement windows, restoring a peaceful bedroom environment while maintaining the character of the original 1890s timber frames.
From first contact to completion in as little as 2 weeks. Most installations are completed in a single day with our same day secondary glazing installation service.
Our expert installer visits your property for a thorough assessment and provides a detailed, no-obligation quote.
What happens during the survey:
✅ You receive:
No high-pressure sales tactics. We aim to provide clarity and confidence.
Book Your Free SurveyUpon your approval, your secondary glazing units are precisely manufactured to your exact window specifications.
✅ What we confirm:
Our skilled and insured installation team transforms your windows, ensuring minimal disruption.
Morning:
Afternoon:
✅ Key benefits:
Most installations are completed within a single day. Larger projects may take two days.
We ensure you're satisfied and provide support for years to come.
Before we leave:
Post-installation:
Total timeline: Approx. 3-4 weeks from survey to installation
Heritage glazing specialists with solutions tailored to your specific property type, from Hampstead townhouses to Kensington apartments
Expert solutions for Victorian and Georgian sash windows
Bespoke panels for complex bay window configurations
Hinged panel solutions for modern casement windows
Luxury Portfolio
A selection of our recent installations in listed buildings, conservation areas, and prestigious period properties.
Grade II Listed Sash Windows
Grade II Listed Sash Windows
Acoustic Overhaul
Acoustic Overhaul
Victorian Bay Windows
Victorian Bay Windows
Georgian Townhouse Restoration
Georgian Townhouse Restoration
Conservation Area Specialist
Conservation Area Specialist
Sash Window Preservation
Sash Window Preservation
Acoustic Casement Glazing
Acoustic Casement Glazing
French Door & Garden Room
French Door & Garden Room
Victorian Bay Sash Installation
Victorian Bay Sash Installation
Transparent Pricing
Straightforward starting prices for the most common configurations. Every quote is bespoke to your property.
Small Casement
per window, fully installed
Ideal for bathrooms, kitchens, and side-facing casement windows in period properties.
Standard Victorian Sash
per window, fully installed
Our most popular configuration for traditional sliding sash windows across London terraces.
Large Georgian Bay
per window, fully installed
Multi-panel bay window systems for grand Georgian and Edwardian reception rooms.
Every installation includes:
Exact costs depend on dimensions and borough-specific planning requirements. All prices include VAT.
Make an Informed Decision
See why 1,200+ London homeowners chose professional installation last year.
2-3mm Acrylic Sheet
Vibrates at traffic frequencies, yellows within months
10.8mm Acoustic Laminated Glass
PVB interlayer converts sound energy into heat
Magnetic Tape Fixings
Peels away from painted frames, zero compression seal
Engineered Aluminium Frames
Precision-machined, powder-coated, compression-sealed
Minimal (15-20 dB)
Traffic, sirens, and aircraft still clearly audible
80% Reduction (up to 54 dB)
Heavy traffic becomes a faint murmur — near-silence
1-Year Lifespan
Acrylic crazes, tape degrades, seals fail after one winter
25-Year Service Life
Optically clear glass, zero maintenance, lifetime warranty
Average customer replaces DIY kits within 14 months
Free survey · No obligation · Same-week availability
2-3mm Acrylic Sheet
Vibrates at traffic frequencies, yellows within months
10.8mm Acoustic Laminated Glass
PVB interlayer converts sound energy into heat
Magnetic Tape Fixings
Peels away from painted frames, zero compression seal
Engineered Aluminium Frames
Precision-machined, powder-coated, compression-sealed
Minimal (15-20 dB)
Traffic, sirens, and aircraft still clearly audible
80% Reduction (up to 54 dB)
Heavy traffic becomes a faint murmur — near-silence
1-Year Lifespan
Acrylic crazes, tape degrades, seals fail after one winter
25-Year Service Life
Optically clear glass, zero maintenance, lifetime warranty
Based on independent testing to BS EN ISO 10140 standards. All professional installations include a lifetime warranty.
Drag the slider to simulate your noise environment and see how our acoustic glazing transforms your Kensington, Westminster or Hampstead home.
Without Glazing
75 dB
Heavy traffic
With Secondary Glazing
21 dB
Whisper quiet
Your noise reduction with our 10.8mm Stadip Silence glass + 100mm air gap
54 dB
Reduction
72%
Quieter
Specialist knowledge of heritage properties, conservation area regulations, and planning requirements in every London borough.
W1 - Georgian townhouses & period properties
Secondary Glazing ChelseaSW3 - Heritage homes & stucco facades
Secondary Glazing WestminsterSW1 - Listed buildings & conservation areas
Secondary Glazing BelgraviaSW1 - Georgian terraces & garden squares
Secondary Glazing KensingtonW8 - Victorian villas & conservation areas
Secondary Glazing KnightsbridgeSW7 - Premium acoustic glazing
Secondary Glazing Notting HillW11 - White stucco terraces & sash windows
Secondary Glazing MaryleboneW1 - Regency properties & noise reduction
NW3 - Conservation area & listed buildings
Secondary Glazing St John's WoodNW8 - Regency villas & mansion flats
Secondary Glazing HighgateN6 - Georgian & Victorian properties
Secondary Glazing Primrose HillNW1 - Regency villas & pastel terraces
Secondary Glazing CamdenNW1 - Victorian terraces & noise reduction
Secondary Glazing Belsize ParkNW3 - Edwardian mansion blocks
Secondary Glazing Holland ParkW11 - Grand Victorian townhouses
Secondary Glazing RichmondTW9 - Flight path & riverside properties
Secondary Glazing GreenwichSE10 - UNESCO heritage quarter
Surrey - Country estates & period homes
Secondary Glazing Virginia WaterSurrey - Crown Estate heritage homes
Secondary Glazing WindsorBerkshire - Royal Borough historic town
Secondary Glazing AscotBerkshire - Country houses & period windows
Secondary Glazing BeaconsfieldBucks - Old Town conservation area
Secondary Glazing St AlbansHerts - Cathedral city heritage properties
Secondary Glazing SevenoaksKent - Listed buildings & Knole Park
We install secondary glazing across all London boroughs, from Westminster and Mayfair to Richmond and the Home Counties. Experts in listed building secondary glazing, acoustic noise reduction, and EPC improvement for period properties.
Technical knowledge and practical advice covering acoustic performance, EPC ratings, listed building regulations, and pricing.
Acoustic Deep Dive
How 10.8mm Stadip Silence glass and a 100-150mm air gap achieve up to 54dB noise reduction. Technical data, lab results, and real-world case studies from Marylebone to Kensington.
EPC Upgrade Guide
Data-driven guide showing how secondary glazing reduces heat loss by 60% and lifts EPC ratings by 1-2 bands. Essential for landlords meeting the 2028 minimum C requirement.
Heritage & Listed Buildings
Why no planning permission is typically required, how we work with conservation officers in Westminster and Chelsea, and how to preserve period features while gaining modern performance.
Price Calculator
Get an instant, no-obligation estimate for your property. Factor in window type, glazing option, and property size for an accurate London price.
Expert Knowledge
In-depth answers from our installation specialists, organised by the four areas that matter most.
Book your free installer survey today. Certified installation specialists with no obligation quotes guaranteed.