Timber
Sash
Windows
Bespoke Timber Sash Windows Built for Performance and Heritage
Timber sash windows designed with the same precision and attention to detail found across all our joinery. Each window is made to measure from sustainably sourced timber – engineered for strength, stability, and enduring performance.
Whether you’re restoring a period property or upgrading a modern home, our sash windows combine authentic proportions with advanced glazing and smooth operation – built to last and beautifully suited to London’s architectural style.
Tradition Refined for Modern Living
Timber sash windows remain one of the most recognisable features of British architecture – defined by balance, proportion, and light. At Sash Window Shop, we build new sash windows that respect original character while delivering the quiet comfort and energy performance expected today.
Each window is made to measure using sustainable timber and advanced glazing, available in both double and vacuum-insulated options. Designed for homes across London, the South East, and the Home Counties, our sash windows combine architectural integrity with everyday ease of use.
Glazing Bar Configurations
Georgian (6 over 6), Victorian (2 over 2), Edwardian, margin bars, and custom patterns.
Our double- and vacuum-glazed units use internal duplex spacer bars to replicate the depth of true through-bars for an authentic look.
Designed Around Your Home
Every sash window is built to order – shaped by your property, your taste, and the architectural story of your home.
Every property is unique, so we offer both traditional and modern sash mechanisms.
Hidden Spiral Balance
A clean, contemporary mechanism where the balance is built into the frame. It removes the need for visible weights or boxes, creating slimmer sightlines and improved airtightness. Ideal for new builds, contemporary renovations, or projects requiring PAS 24 compliance.
Explore Our Spiral Balance Sash Window Specification
For a closer look at our hidden spiral balance sash windows – including operation details, technical drawings, and full specification options – visit our dedicated specification page below.
Cords & Weights
Our classic counterweight system preserves the traditional movement of a true sash window. Precision-engineered pulleys and solid brass weights deliver smooth, balanced travel. This option is perfectly suited to listed buildings and conservation area homes seeking authentic operation.
Learn More About Our Cords & Weights Sash Window Specification
Discover the full specification for our traditional cords and weights sash windows – including section profiles, glazing details, and CAD drawings. Visit the dedicated page below to explore design options and technical information.
Key Features of Our Timber Sash Windows
Every Sash Window Shop product is designed to combine traditional detail with modern performance, delivering genuine long-term value for your home.
- Choice of Mechanism – Hidden spiral balance or traditional cords & weights systems to suit any property type.
- Centre-pane U-values from 0.4 W/m²K with vacuum glazing
- Slim, authentic sightlines suitable for conservation work
- Designed and tested to meet current Building Regulations (Part L compliant)
- Option to upgrade to PAS 24:2022 tested for enhanced security
- Factory-Finished Excellence – Teknos 4-coat microporous paint system applied under controlled conditions for maximum longevity and colour consistency.
- Discreet Ventilation – Optional hidden trickle vents integrated within the frame head to meet Building Regulations without affecting appearance.
- Heritage Detailing – Multiple mould profiles, glazing bar layouts, and horn designs to replicate original joinery across Georgian, Victorian, and Edwardian styles.
- Advanced Glazing Beads – Internally glazed for security, with precision-cut beads and seals for a refined internal finish (externally glazed options available).
- Comprehensive Guarantees – Insurance-backed warranties for full peace of mind.
Each wooden sash window delivers the character of traditional timber windows with the assurance of tested modern standards.
Traditional Moulds and Astragal Glazing Bars
Recreate period accuracy or introduce subtle modern symmetry through our full range of glazing bar and moulding options.
Moulding Profiles
Choose from Ovolo or Lamb’s Tongue sections, available in 17 mm, 20 mm, 22 mm, or 26 mm widths. Each profile is CNC-cut for precision and finished to match existing joinery where required.
Astragal Bars
Our astragal glazing bars recreate the traditional appearance of through bars while incorporating modern manufacturing techniques for strength and performance.
Each window uses a solid outer glazing cassette built directly into the sash or frame, forming a rigid and secure structure. The double-glazed unit is set behind this cassette, locking it firmly within the profile for improved protection and stability.
Once glazed, the internal mould profiles are applied to complete the authentic appearance, creating the visual effect of individual panes while maintaining full thermal and acoustic performance.
This construction method provides excellent security, longevity, and detailing, with every bar precisely aligned to achieve perfect symmetry across the sash.
Our quality & service are very important to us…
What Our Customers Say
We’re proud to be rated Excellent on Trustpilot, with genuine feedback from our clients who have chosen our timber windows and doors windows.
Twelve Sash Horn Designs
Select from twelve distinctive horn shapes inspired by regional and historical joinery. From slender late-Victorian horns to deeper Georgian and Edwardian profiles, every design is engineered for accuracy and visual balance. Supplied primed or factory-finished, each horn completes the authentic appearance of a traditional timber sash.
Conservation and Planning Expertise
Installing new sash windows in a conservation area or listed property requires precision, understanding, and documentation — all of which we provide as standard.
Our team regularly supports homeowners, architects, and conservation officers across London, Hertfordshire, and the Home Counties. We prepare Heritage Statements, detailed CAD elevation drawings, and specification sheets to assist planning submissions and approvals.
We work within Article 4 conservation guidelines, ensuring each replacement respects original proportions, glazing patterns, and joinery detailing.
Whether you need like-for-like replacements or an energy-efficient upgrade, our planning experience ensures compliance with local authority requirements and a smooth approval process.
Discreet Hidden Trickle Vents
To maintain ventilation without compromising design, we integrate hidden trickle vents within the head of the frame.
These vents meet current Building Regulation requirements for airflow while preserving original sightlines — a subtle detail that protects your warranty and aesthetics simultaneously.
Glazing Options for Every Project
From standard double glazing to cutting-edge vacuum glass, each option is tested for acoustic and thermal performance.
Double glazing (standard) – Excellent insulation and everyday energy savings
Vacuum glazing (premium) – Ultra-slim 8.3 mm units achieving centre-pane U-values as low as 0.4 W/m²K
Single glazing (heritage) – True-to-period appearance for listed properties
Acoustic glass – Reduces external noise for quieter city living
Laminated or toughened glass – Extra security and impact resistance
Reeded or satin glass – Decorative and privacy options for bathrooms or stairwells
All glazing types are supplied fully sealed, certified, and ready for installation.
Paint and Finishes
Every sash window is factory-finished using the Teknos four-coat microporous system, providing maximum protection, colour stability, and breathability.
Key benefits of our finishing system:
Full factory coating — no site finishing required
Excellent UV resistance and moisture control
Colour-matched to any RAL, Farrow & Ball, or Little Greene shade
Smooth, even film thickness across all surfaces
Environmentally friendly water-based coatings
Dual-colour finishing is available where exterior and interior colours differ – perfect for homes where you’d like a crisp white interior and a heritage tone externally.
Our controlled spray-finish process ensures consistent coverage across every component, providing a finish that complements both traditional and contemporary architecture.
Hardware and Security
To maintain ventilation without compromising design, we integrate hidden trickle vents within the head of the frame.
These vents meet current Building Regulation requirements for airflow while preserving original sightlines — a subtle detail that protects your warranty and aesthetics simultaneously.
For those seeking a more refined finish, we also offer a Deluxe range of architectural ironmongery from Croft and From the Anvil — two of Britain’s leading manufacturers. Their handcrafted collections include polished brass, antique bronze, and satin nickel pieces, providing an elevated level of detailing for high-end residential and heritage projects.
Discover Our Deluxe Hardware Collection
For a more refined finish, explore our Deluxe range of architectural ironmongery from Croft and From the Anvil.
These British manufacturers are renowned for their craftsmanship, producing handles, pulleys, and locks in a range finishes.
Their ranges are designed to complement both period and contemporary sash windows, offering exceptional tactile quality and long-term durability.
Design Your Timber Sash Windows
Every property deserves sash windows that complement its architecture.
Our design process gives you full control over appearance, operation, glazing, and detailing — ensuring your timber sash windows deliver the perfect balance of period authenticity and modern performance.
We create every window to order, combining design flexibility with structural integrity, precision joinery, and long-term durability.
Timber Selection
Ironmongery Finishes
Exceptional Security and Hardware
Glazing Options
Bespoke
Endless Colour Choices
Sash Horn Designs
Design Your Timber Sash Windows
See Our Windows in Real Homes
From Maida Vale and Hampstead to Berkhamsted and Islington, our sash windows feature in some of London’s most characterful homes. View real installations and discover how traditional proportion meets modern performance in every project.
Tested for Performance and Approved for Planning
Hidden spiral balance windows meet PAS 24 security standards.
Our standard double glazed units are energy tested, with U-value reports available.
Vacuum and single glazing options are suitable for conservation areas and heritage projects. We also supply supporting specification documents for planning applications.
If you’re unsure what type of glazing or sash style you need, we’re happy to advise.
Timber Options
Our sash windows are built from premium engineered timber, chosen for its strength, dimensional stability, and long service life. Every piece is laminated and finger-jointed to resist warping and movement, ensuring your windows stay straight and true through changing seasons.
Available timber species:
Redwood Pine – A stable, fine-grained softwood that offers excellent value and paint adhesion. Ideal for standard specifications.
Meranti – A dense, durable tropical hardwood with a smooth surface and consistent colour tone, providing a refined finish for painted or stained applications.
Sapele – A richly coloured hardwood with interlocking grain and high durability, suitable for both paint and stain finishes.
Oak – Traditional and enduring, with a distinctive grain pattern. Oak provides natural strength and is often chosen for feature joinery or exposed interiors.
Accoya – A high-performance modified softwood with a 50-year warranty against rot. Outstanding dimensional stability and resistance to moisture make it ideal for London’s changing climate and for projects seeking minimal maintenance.
View our wooden sliding sash windows up close
Get in touch today
We’d love to hear from you!
If you have any questions or would simply like some more information about our high performance timber windows & doors, then simply fill in the form below and we will be in touch.
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