Deceuninck Heritage Flush Sash Windows
Authentic flush timber-look windows for heritage and modern homes
The Deceuninck Heritage Flush Sash is the definitive choice for homeowners who want the unmistakable look of a traditional timber window without the maintenance — or the carbon footprint. Internally and externally flush, with authentic 19th-century proportions, ovolo glazing detail, and the deep mechanical-jointed corners of the original timber casements it replaces.
Specified across some of Staffordshire's most sensitive conservation areas, Heritage Flush Sash is approved for use in listed and period properties — yet delivers contemporary thermal, security and weather performance that timber simply cannot match.
Every Heritage installation by SGS is hand-finished, individually surveyed and installed by our own time-served fitters. The result: heritage character that lasts, performance you can feel, and kerb appeal that turns heads.
Why choose Deceuninck Heritage Flush Sash Windows
- Authentic flush profile inside and out — indistinguishable from timber at a distance
- Approved for conservation areas and many listed properties
- 70mm 6-chamber profile with A+ thermal rating as standard
- Mechanical-jointed corners replicate traditional joinery
- Maintenance-free for 35+ years — no painting, sanding, or rotting
- PAS24:2016 Secured by Design accreditation
- Available in 26 manufacturer colours including authentic timber-look foils
Engineered for performance
- Fully reinforced sash and frame for structural longevity
- Yale multi-point locking with anti-snap cylinders
- Internally beaded — glass cannot be removed from outside
- Argon-filled, soft-coat low-E sealed units
- Monkey-tail or pear-drop heritage handles included
- Optional Georgian bars, leaded glass and stained-glass details
- High-grade EPDM gaskets eliminate drafts and water ingress
Configurator
Mix and match colours, hardware and glass to suit your home.
Available finishes
Choose your style
- Side-hung casement
- Top-hung opener
- Fixed light
- Bay (square or splayed)
- Bow
- French casement (two-leaf, no centre mullion)
Glass options
- Argon-filled double glazing — A+ rated
- Triple glazing for ultra-low U-values
- Acoustic interlayer for noise reduction
- Solar-control low-E coatings
- Decorative leaded, Georgian bar and stained options
- Obscure privacy glass for bathrooms
- Toughened safety glass to BS EN 12150
Furniture & hardware
- Yale multi-point locking with anti-snap, anti-pick, anti-bump cylinders
- Heritage monkey-tail and pear-drop handles
- Modern lever-action handles
- Concealed hinges with restrictor option
- Brass, chrome, satin and matt-black finishes
- PAS24:2016 Secured by Design accreditation
The Heritage Flush Sash achieves a Window Energy Rating of A++ as standard — the highest available — with whole-window U-values down to 1.2 W/m²K. Triple glazing further reduces this to 0.8 W/m²K, exceeding new-build Building Regulations.
For heritage properties this matters: replacing timber single-glazing typically reduces heat loss through the windows by 75–90%, with EPC ratings improving by one or two bands.
Engineered to protect
Heritage doesn't mean vulnerable. Every Heritage Flush Sash window is internally beaded — meaning the glass cannot be levered out from outside — and ships with Yale multi-point shootbolt locking and anti-snap, anti-pick, anti-bump cylinders to PAS24:2016.
For policyholders insured under the ABI Secured by Design discount scheme, our Heritage Flush Sash specification qualifies for premium reductions with most major UK insurers.
Tailored to your home
From astragal bar configurations to authentic monkey-tail handles in polished chrome, brass or matt black — every Heritage installation is built around your home. Choose ovolo or chamfered glazing detail, square or splayed bay corners, and any combination of fixed, top-hung and side-hung openers.
Property suitability
Designed for Victorian and Edwardian terraces, 1930s semis, period cottages, listed buildings and conservation-area properties where authentic detailing is essential. Equally at home on contemporary new-builds where homeowners want the warmth of traditional design with modern performance.
How we fit it
Each window is precisely surveyed, manufactured to ±1mm tolerances, and installed by our own teams in 1–2 days. We protect floors and furnishings, fit silicone-and-foam weatherseals to current FENSA standards, and remove all old materials for recycling. You'll have your FENSA certificate within 30 days.
Frequently asked
Will Heritage Flush Sash windows be approved in a conservation area? +
How does the Heritage profile differ from a standard flush window? +
How long does installation typically take? +
Do you offer a guarantee? +
Can I match my existing windows or doors? +
Are your installers FENSA registered? +
Like the Deceuninck Heritage Flush Sash Windows? Let's talk.
Free home survey across Staffordshire — typically booked within 48 hours.