Secondary Glazing Sliding Sash Units Manufactured in the UK
Our bespoke timber secondary glazing sliding sash units are handcrafted in the UK to improve thermal efficiency, reduce noise and minimise draughts without replacing your existing sash windows.
Designed specifically for listed buildings, conservation areas and period properties, these discreet internal secondary glazing systems retain the character and appearance of the original windows while delivering significant improvements in comfort and performance.
Each secondary glazing unit is manufactured to your exact sizes using slim timber profiles and smooth spring-balanced sliding systems, allowing natural light and traditional detailing to remain uninterrupted.
Discreet Secondary Glazing for Period & Listed Properties
Secondary glazing sliding sash units are installed internally behind the existing window, creating an additional insulating barrier without altering the external appearance of the property.
This makes them an ideal solution for heritage properties where replacing the original sash windows may not be permitted or desirable.
Our timber secondary glazing systems are suitable for:
- Listed buildings
- Conservation areas
- Georgian and Victorian homes
- Edwardian properties
- Period refurbishments
- Traditional sash windows
- Noise reduction projects
- Properties requiring improved thermal efficiency
Why Choose Timber Secondary Glazing?
Secondary glazing is one of the most effective ways to improve the performance of existing timber sash windows without replacing original joinery.
Unlike full window replacement, secondary glazing preserves the architectural character of the property while providing substantial improvements in thermal insulation, acoustic performance and draught reduction.
Our timber secondary glazing sliding sash units offer:
- Discreet slim-profile timber construction
- Improved thermal performance and reduced heat loss
- Excellent acoustic insulation
- Reduced draughts and condensation
- No external visual changes to the property
- Smooth spring-balanced sliding operation
- Fully bespoke sizing
- Suitable for listed buildings and conservation areas
Design & Performance
Every secondary glazing unit is designed with slim, unobtrusive timber sections to maximise natural light while maintaining the appearance of the original window.
The smooth sliding sash mechanism allows practical ventilation and access for cleaning while preserving clean sightlines and traditional detailing.
Secondary glazing provides significant improvements in:
- Thermal insulation
- Acoustic performance
- Draught reduction
- Condensation control
- Overall comfort within the property
All systems are designed to integrate neatly within the existing window reveal with minimal visual impact.
Key Features
- Slim timber secondary glazing system
- Spring-balanced sliding sash operation
- Designed to maximise natural light
- Ideal for listed buildings and conservation areas
- Improves thermal efficiency and reduces heat loss
- Excellent acoustic performance
- Reduces draughts and condensation
- No external visual changes to the property
- Manufactured to bespoke sizes
- Smooth premium joinery finish
- Manufactured in the UK
Suitable for Projects Large & Small
We manufacture bespoke timber secondary glazing units for projects throughout the UK, including:
- Single sash window upgrades
- Listed building refurbishments
- Conservation-area properties
- Period home renovations
- Acoustic improvement projects
- Energy-efficiency upgrades
- Heritage refurbishments
- Complete property secondary glazing packages
Timber Options
We offer a range of premium timber species suitable for secondary glazing applications, including:
- Redwood
- Sapele
- Tulipwood
- FSC® certified timber options
Additional timber species may also be available depending on project requirements.
Glazing Options
All glazing is carefully selected to balance performance, weight and minimal sightlines while preserving the appearance of the existing window.
Typical glazing options include:
- Laminated single glazing
- Vacuum-sealed glazing units for enhanced thermal performance
All glazing is installed within slim, light-maximising timber profiles designed to preserve the original character of the window opening.
Hardware Options
We supply high-quality sliding hardware systems selected for smooth operation and long-term durability.
Available options include:
- Spring-balanced sliding systems
- Locking options where required
- Brush seals and draught-reduction systems
Factory Finishing Options
Our timber secondary glazing units can be supplied fully factory-finished or prepared for on-site decoration depending on project requirements.
Available finishing options include:
- Primed for on-site finishing
- Fully factory painted
- Clear lacquer finishes
- Stained and tinted finishes
Factory finishing is available in a wide range of colour options using durable microporous coating systems for long-lasting protection and a smooth premium finish.
Bespoke Joinery Capabilities
As a bespoke joinery manufacturer, we can produce fully customised timber secondary glazing units tailored to your project requirements, including:
- Shaped and arched secondary glazing units
- Large-format secondary glazing systems
- CAD drawings for approval
- Integration with shutters and existing trims
Lead Times
Typical lead times for bespoke timber secondary glazing sliding sash units are approximately 6–8 weeks depending on project size, specification and finishing requirements.
Estimated lead times are confirmed at quotation stage.
Request a Quote for Secondary Glazing Sliding Sash Units
Whether you require secondary glazing for a single sash window or a complete listed-building refurbishment project, our team will be happy to assist.
Send us your drawings, measurements, schedules or project details and we will prepare a detailed quotation tailored to your specification.
Call us on 0191 535 9563 or email info@timbermouldingsdirect.co.uk.