Sliding Sash Windows Classic Elegance with Modern Performance
At Win-Doors INT LTD, our uPVC and Aluminium sliding sash windows bring timeless vertical sliding charm with A-rated energy efficiency, smooth operation, and authentic heritage details. Perfect for period, Victorian, and Georgian properties across London.
Authentic detail: Our equal sightlines and 19mm astragal bars replicate original timber flush casements for conservation approval in London boroughs.
What is a Sliding Sash Window?
A sliding sash window is a classic window style where two sashes slide vertically past each other within the frame. Unlike casement windows that open outwards on hinges, sash windows operate with a balanced sliding mechanism using spiral balances or traditional weights.
Originally found in Georgian, Victorian and Edwardian homes, our modern uPVC sliding sash windows replicate that heritage look with authentic features like run-through horns, deep bottom rails, and astragal bars, but with modern benefits — no rattling, no draughts, no painting needed.
- Flush: sash sits level, no lip, clean shadow line, authentic heritage look
- Timber origin: replicates 19th-century joinery, now in uPVC, aluminium and timber
Key Features of Our Sliding Sash Windows
Engineered for heritage aesthetics and modern Building Regulations compliance.
Authentic Heritage Design
Run-through sash horns, slim meeting rails, deep bottom rail, and putty-line aesthetics for a true timber appearance.
Energy Efficient
Double or triple glazing, high-performance seals and A-energy ratings to reduce heat loss and energy bills.
Enhanced Security
Secured by Design option, multi-point locking, anti-jemmy bars and PAS 24 compliance.
Smooth Vertical Sliding
Advanced spiral balance system for effortless, fingertip operation and tilt facility for easy cleaning.
Low Maintenance
No sanding, painting or warping. Woodgrain or smooth finishes that last for years.
Customisable & Symmetrical
Equal sightlines, heritage colours, traditional hardware.
Benefits of Sliding Sash Windows
Chosen by architects for conservation areas and design-led new builds for its timeless proportions.
For Heritage & Conservation
Ideal for listed buildings, conservation areas, and period properties in London. Like-for-like timber replacement approved.
Better Ventilation Control
Open from top or bottom to control airflow while maintaining security.
Space Saving
No outward opening — perfect for properties near walkways, roads or balconies.
Timeless Value
Adds character and increases property value, blending classic style with modern comfort.
Weatherproof & Quiet
Draught-free, weather-tight seals with optional acoustic glazing for busy London homes.
Our Sliding Sash Window Range
All made-to-measure in our London workshop partnership. Choose based on conservation needs, budget, and aesthetic.
uPVC Sliding Sash Windows
Our most popular. Authentic woodgrain finish, A-rated, cost-effective, and low maintenance. Available in white, cream, Chartwell Green, Anthracite Grey, Black, and dual colour.
- Woodgrain & smooth finishes
- 30+ colours, dual-colour option
- Conservation-friendly for most boroughs
Aluminium Sliding Sash Windows
Contemporary sash look with ultra-slim aluminium strength for modern and heritage-new-build mix.
- 54mm ultra-slim sightlines
- Flush interior & exterior
- 200+ RAL colours, anodised options
Perfect For Every Property Type
Specified by architects across London for their authentic proportions and clean lines.
Victorian & Georgian Homes
Restore original character while upgrading performance.
Period Terraces in London
Most common in UB1, Southall, Ealing, Harrow authentic replacement.
Conservation Areas & Listed Buildings
Council-approved designs with heritage details.
Customise Your Sash Windows
Every window made-to-measure. Mix colours, glazing, and heritage hardware to match your property.
Smooth, woodgrain, dual-colour. 30+ options.
- Smooth or woodgrain foil.
- Double glazed 28mm,
- Acoustic & Triple glazed
- Toughened & Obscured.
- Georgian bars
- Astragal bars
- Run through horns
- Decorative horns
- Traditional brass
- Chrome & Black
- Satin including D-handles
- Pole eyes & Sash lifts.
- Frosted
- Leaded
- Acoustic for noise reduction.
Our Sliding Sash Installations in London
Authentic Sliding Sash detailing in period and modern properties.
Why Choose Win-Doors INT LTD for Sliding Sash Windows in London?
Made to Measure in our UK factory. Professional installation across London & Greater London. A-Rated & Building Regs Compliant (Document L). 10-Year Guarantee. Free Home Survey, Design Consultation & Brochure. Over 15+ Years Experience in heritage windows.
- Made-to-measure in partnership with UK fabricators
- Professional installation, London & UK wide, FENSA registered fitters
- A-Rated, Building Regulations Part L compliant, BFRC certified
- 10-year insurance-backed guarantee on all flush casement windows
- Free consultation & survey, technical drawings for planning
500+Sliding Sash Installs in London
From Clapham to Highgate, conservation terraces to new builds.
FENSA, Certass, Secured by Design accredited installers.
PAS 24, Part L, BFRC certified, Yale locking as standard.
Same-week appointments. Detailed quote within 24 hours.
Sliding Sash Windows - Frequently Asked Questions
Answers to the questions homeowners ask us most about uPVC, aluminium and heritage flush casements.
What is the difference between sash and casement windows?
Sash windows slide vertically, casement windows are hinged and open outwards. Sash is traditional, casement is more modern.
Are uPVC sash windows suitable for conservation areas?
Yes, our heritage uPVC sash windows with run-through horns and slim meeting rails are approved as like-for-like replacements in many London conservation areas.
Are sliding sash windows energy efficient?
Yes. Our A-rated double-glazed sash windows with warm-edge spacers and Q-Lon seals prevent draughts and reduce energy bills.
How do you clean sliding sash windows?
Both sashes tilt inwards for safe cleaning from inside your home no ladders needed.
How much do sliding sash windows cost in London?
Cost depends on size, material and glazing. uPVC sash starts from more affordable than timber. Contact us for a free, fixed quote.
Restore Your Home's Character with Sliding Sash Windows
Transform your property with elegant, energy-efficient sliding sash windows from Win-Doors INT LTD London. Get your free survey and quote today.