WE MANUFACTURE
Every Sash Vault window is custom-made in our UK facility
At Sash Vault, we don’t modify standard frames. We manufacture each window from scratch – around your property, your proportions, and your priorities.
Every unit is built in-house by our specialist joinery team. We combine traditional woodworking skills with engineered precision to produce sash windows that look authentic, move beautifully, and protect silently.
We control the full process – design, material selection, engineering, and finishing. This allows us to match exact architectural details, deliver any size or shape, and ensure our patented stainless steel reinforcement is fully concealed within each frame.
We don’t outsource. We don’t cut corners. We don’t rely on assumptions. Whether you require arched Georgian bays, oversized double sashes, or windows for a Grade 2 listed façade – we manufacture them exactly to spec, exactly as they should be.
We design each window around your architecture
Your home is not generic – your windows shouldn’t be either. At Sash Vault, every frame is made to order, to the exact dimensions, sightlines and curvature of your property.
We begin with a detailed on-site survey, ensuring that every measurement and architectural nuance is captured with precision. Whether your project involves a heritage terrace, a country home, or a modern build with traditional styling – we adapt the construction entirely to fit.
There are no set modules, no standard widths, and no maximum sizes. We produce oversized frames, arched tops, slim sashes, asymmetrical pairs, and full bay assemblies – all built in-house to match your plans.
The result is a window that fits your building not only in size, but in proportion, rhythm, and heritage detail. Every reveal, line and joint aligns naturally – because the entire product was crafted with your property in mind.
Security doesn’t limit usability – it enhances it
We manufacture sash windows that suit your lifestyle as much as your architecture. Whether you prefer a classic top-and-bottom sash layout or a more tailored single-sash configuration, our joinery allows complete flexibility.
Each window can be designed to slide from the top, bottom, or both, depending on your space, access, and ventilation needs. Internally balanced and professionally weighted, every sash moves smoothly and sits securely – even in larger formats or non-standard openings.
We ensure that the opening style fits your room’s use and your building’s heritage. Bedrooms, bathrooms, upper floors, and street-facing rooms may all require different functionality – and we build accordingly.
Security and strength are never compromised. Our patented internal structure supports all movement styles, with concealed resistance and engineered glide, so your windows stay elegant in form – and solid in function.
Our manufacturing adapts to your building’s design
Your property’s lines and proportions deserve to be respected – not forced to fit a pre-set system. That’s why we manufacture sash windows in any shape, size, or curvature required. Whether restoring heritage geometry or introducing bold architectural features, we shape our joinery to suit.
We routinely produce arched heads, sweeping bays, rake-top sashes, oversized panels, and tall or narrow forms – each engineered to match your elevation with millimetre precision.
Each unit is fully drawn, specified, and approved before it enters production. Our skilled craftsmen shape every curve, mitre and frame joint by hand, ensuring the final window feels as if it has always belonged.
The internal steel structure is adapted to each shape, reinforcing performance without altering the outer lines. No compromises on appearance. No limitations on design.
If your building demands precision and individuality, this is where form and function meet.
Choose from single, double, UV, acoustic or ballistic glazing
At Sash Vault, glazing is never an afterthought. It’s a vital part of the system – one we customise to meet both aesthetic and performance needs.
We offer a full range of single and double glazing options, including low-E, UV-reflective, acoustic, and laminated glass. Whether you require heritage-style putty-glazed panes or modern insulated sealed units, we build the window around the right specification for your home.
For clients with elevated risk profiles, we provide bullet-resistant glazing, fully integrated into our patented sash structure. This option combines discreet appearance with certified ballistic resistance – ideal for embassies, high-value homes or city residences needing silent security.
All units are professionally sealed and tested for thermal stability, clarity, and long-term performance. Edges are protected. Sightlines are preserved. And everything is installed within our handcrafted timber frames with precise, seamless finish.
Whether your priority is planning compliance, energy performance, or personal safety, we have the right glazing – and we install it with care.
We combine the finest timber with a concealed steel core
What makes a Sash Vault window different isn’t just how it looks – it’s what lies beneath. While the exterior is made from premium engineered timber, the interior houses a welded stainless steel structure, completely concealed, yet central to its performance.
We use Accoya and Medite Tricoya – industry-leading materials chosen for their stability, durability and weather resistance. These timbers are dimensionally stable and resistant to rot, warping and shrinkage – essential for long-term sash movement and sealed glazing.
Inside, our EU-patented steel core forms the load-bearing skeleton of the window. It strengthens the frame, resists physical attack, and allows integration of security components without compromising the traditional look. You’ll never see the structure – but you’ll know it’s there.
This unique combination of natural finish and engineered power allows us to deliver sash windows that glide smoothly, last for decades, and resist forces no normal timber frame could tolerate.
The result is true timber craftsmanship – underpinned by solid structural logic. Beautiful to look at. Impossible to break.
Our patented system allows safe, secure ventilation day or night
Traditional sash windows offer beautiful movement – but leave no safe way to ventilate. At Sash Vault, we solved that. Every window we manufacture includes our patented secure ventilation lock, a built-in feature that allows you to leave the sash slightly open – without inviting risk.
This innovation holds the sash in a fixed open position, allowing air to flow in while the frame remains securely locked. It’s particularly useful in bedrooms, bathrooms, or anywhere regular airflow is needed without sacrificing peace of mind.
There are no unsightly additions. The mechanism is discreet, designed into the frame, and does not affect the visual appearance of the window. It’s secure against external force and fully integrated into our reinforced structure.
No other sash window on the market combines heritage compliance with this level of passive protection. It’s one of many features that sets Sash Vault apart – thoughtful, elegant, and quietly effective.
Every visible detail respects your building’s character
At Sash Vault, appearance is never an afterthought. Every window we manufacture is crafted to look architecturally correct – especially where heritage or listed status demands precision.
We replicate original sash detailing with millimetre-level accuracy: from horn shapes and glazing bar profiles to putty lines, cord operation, and period-specific joints. The result is a window that sits naturally within Georgian, Victorian or Edwardian façades – without drawing attention to itself.
This visual authenticity is what earns our product approval for Grade 2 listed buildings – the only sash window system in the UK with this status.
But behind this heritage appearance lies modern, engineered strength. Our security features and structural steelwork are entirely concealed, allowing your home to meet conservation standards without sacrificing safety, glazing options, or long-term performance.
We don’t imitate heritage joinery. We honour it – and reinforce it from within.
Every window is touched, tested, and approved by our team
We build everything ourselves. No outsourcing, no assembly lines, no third-party shortcuts. Every secure sash window is manufactured in our own UK facility, by skilled craftsmen who specialise in secure timber joinery.
Our workshop is where heritage design and patented construction come together. From the first cut of engineered timber to the final fitting of locks and glazing, each step is handled by trained joiners and engineers who understand the responsibility behind every frame.
We don’t ship parts in. We don’t buy blanks. We craft, assemble and finish every element to our own specification – because only that gives us the control, consistency and confidence to deliver at the level our clients expect.
Before any window leaves our facility, it is thoroughly inspected for quality, strength, movement and finish. If it isn’t perfect, it doesn’t go out.
This is manufacturing the way it should be: slow where it needs to be, fast where it can be – always right the first time.
One visit says more than any brochure
Some things can’t be shown on a website. The weight of the sash. The glide of the movement. The feel of true timber. The silence of concealed strength.
That’s why we welcome you to visit our showroom, by appointment. You’ll see our windows fully assembled and functioning – exactly as they would be in your home. Test the locks. Inspect the joints. Examine the finishes. Open, close, and listen to how secure feels.
We’ll walk you through materials, glass options, opening styles, and explain what’s happening beneath the surface – where our patented structure lives, invisible but essential.
Prefer we come to you? You can also book a professional survey, where our team visits your property, takes precise measurements, and prepares a tailored proposal based on your layout and needs.
59 Chalton St
London, NW1 1HY