Vacuum glazing cost in the UK: an honest buyer's guide
When people ask what vacuum glazing costs in the UK, they usually want a single number. There isn't one — and any guide that hands you one is either guessing or selling something. Vacuum insulated glazing (VIG) is a made-to-measure pane fitted into made-to-measure joinery, so the "price" bends around the glass you choose, the size and number of units, whether the frames stay or go, and who does the fitting. What this guide offers instead is honest context: the factors that move the bill, some indicative market ballparks, and how VIG stacks up against the alternatives you are really weighing it against.
One thing to fix in your mind before any figure appears below. Everything here is an indicative market estimate drawn from installer blogs, distributor pages and third-party market summaries. None of it is a quotation, and none of it should be treated as one. Prices move with size, specification, exchange rates, shipping and labour rates, and they date quickly. For your actual windows, only an itemised written quote from a fabricator or installer counts.
Why there is no single price
The first confusion to clear up is what you are even pricing. “Vacuum glazing cost” can mean two very different things.
The glass unit on its own is the sealed VIG panel — two panes of glass with a sub-millimetre evacuated gap, held apart by a grid of tiny support pillars and sealed at the edge. Fabricators buy these by the square metre, or as cut-to-size units, and a bare-unit price is what most online figures refer to.
The whole job is what actually lands on your invoice: the glass, plus survey and measuring, plus the joinery work to accept a slim VIG unit into an existing sash or casement (or a new frame built around it), plus removal of the old glass, glazing labour, beads and finishing, waste disposal, scaffolding or access where needed, and VAT. On a heritage retrofit the labour and joinery can rival or exceed the glass itself.
So when someone quotes “£120” and someone else quotes “£900 a window,” they may both be right — they are simply pricing different things. Throughout this guide we try to be explicit about which is which, because conflating them is the single biggest reason homeowners feel misled on cost.
Rule of thumb, heavily hedged: as an indicative market estimate, VIG tends to run around two to four times the cost of standard double glazing — but that gap narrows sharply against triple glazing, and can invert entirely once you factor in keeping versus replacing your frames.
What actually drives the cost
Several levers push a VIG project up or down. Understanding them lets you read a quote critically rather than just reacting to the total.
Size and the number of units
VIG is priced largely by area, so a run of tall Victorian sashes costs more in glass than a handful of small cottage casements. But it is rarely a clean per-square-metre multiplication: very small units carry a minimum charge, and very large or unusually shaped units can attract a premium or hit a manufacturer’s maximum size. The number of separate openings also matters, because each one carries its own survey, handling and glazing labour regardless of how much glass it holds.
The product you choose
The main architectural VIG products available in the UK — Pilkington Spacia, AGC Fineo, and LandVac — sit at different points on the price-and-performance curve, with a growing number of Chinese makers (such as HaanGlas and LEADUS) appearing alongside them. First-generation Spacia (centre-of-glass Ug around 1.1 W/m²K) is the original but is widely regarded as surpassed on performance, and it needs an applied safety film rather than coming toughened as standard. Fineo (Ug around 0.7) and the tempered LandVac (Ug around 0.4–0.48) reach into triple-glazing territory. Broadly, the higher-performing and safety-rated products sit at the upper end of the range, though distribution, shipping and fabricator relationships muddy any neat ranking. Our Spacia, Fineo and LandVac comparison digs into how they differ beyond price.
Tempered versus annealed (safety glass)
Where safety glass is required — low-level glazing, doors, sidelights — the answer affects both cost and product choice. Tempered VIG such as LandVac meets safety-glass standards on its own, whereas annealed products like classic Spacia typically need an applied safety film or a laminated make-up to comply, adding cost and steps. Toughening also involves a low-temperature edge seal, which is part of why fully tempered units command a premium.
Hybrid VIG-in-IGU units
A hybrid unit sandwiches a VIG panel together with a third, gas-filled pane inside a conventional insulated glass unit — for example Fineo’s hybrid make-up, which reaches roughly Ug 0.4–0.5 W/m²K but at 22–34 mm rather than a slim 7–8 mm. These deliver the lowest U-values available, but you pay for the extra pane and assembly, and you lose the thin sightline that makes plain VIG so useful in heritage frames. Hybrids make sense where you need Passivhaus-grade numbers and have the rebate depth to house them; they are not the default choice for a slim sash retrofit.
Joinery and installation labour
This is the line item most people underestimate. Dropping a slim VIG unit into a historic timber sash is skilled work — the frame may need routing out to a new rebate depth, draught-proofing, repairs to cords, weights and beads, and careful reinstatement so the finished window still looks right. Not every glazier is experienced with VIG, and heritage joinery is a specialist trade. On a conservation project the fitting and joinery can be the larger half of the bill. This is also why like-for-like comparison between quotes is hard: two installers can price the same glass very differently because they scope the joinery differently.
Listed-building and access complexity
Listed status, conservation areas and Article 4 directions add cost in less obvious ways: conservation-officer consultation, listed building consent applications, mock-ups or sample panels, more conservative (slower) working methods, and sometimes a requirement to retain and repair rather than replace. Physical access matters too — upper-floor sashes, bay windows and anything needing scaffolding or a tower all add to the labour line. If your property is listed, read our note on vacuum glazing for listed buildings alongside this cost guide, because the approvals process shapes both the timeline and the budget.
Indicative ballparks (estimates, not quotes)
With all those caveats loudly in place, here are some figures that circulate in the UK market. Treat them as installer and market estimates, not prices you can hold anyone to.
- A widely cited 2024 global figure puts bare VIG units at roughly US$100–300 per square metre — a manufacturing-side range, before UK import, fabrication, frames or fitting.
- One UK distributor’s material lists Fineo from around £120 per glazing unit, explicitly size-dependent — a glass-only, small-unit starting point rather than an installed price.
- Some UK users of LandVac report figures in the region of £290 per square metre for the glass — again, unit cost, not the installed total.
- As a rule of thumb repeated across UK installers, the whole-project premium works out at roughly 2–4× standard double glazing, with the multiple falling as you compare against triple glazing or against replacing the frames entirely.
The honest takeaway from that spread is that the numbers do not resolve into one clean answer, because they are measuring different things at different points in the supply chain. A £120 bare unit and a £290/m² bare unit and a £900 installed sash can all be internally consistent. The table below is a way to reason about direction — what pushes your particular quote up or down — rather than a price list.
| Cost factor | Typical effect on the price | Why |
|---|---|---|
| Unit area (per m²) | Primary driver | VIG is largely priced by glass area; bigger openings cost more glass |
| Number of separate openings | Adds up quickly | Each window carries its own survey, handling and glazing labour |
| Product line (Spacia / Fineo / LandVac / HaanGlas) | Moderate | Higher-performance and tempered products tend to sit at the upper end |
| Tempered vs annealed / safety glass | Upward where safety glass is required | Toughened units or added safety film cost more than plain annealed |
| Hybrid VIG-in-IGU | Upward, sometimes sharply | Extra gas-filled pane and assembly for the lowest U-values |
| Joinery & installation labour | Often the largest single line | Skilled retrofit into historic frames; repairs, rebating, reinstatement |
| Listed-building / access complexity | Upward, project-specific | Consents, consultation, mock-ups, scaffolding, slower working methods |
| Lead time / shipping | Indirect | Longer or air-freighted supply can add cost and constrain scheduling |
Every entry above is a direction of travel, not a figure. Two projects with the same glass can differ by a wide margin once joinery, access and specification are scoped.
The premium over double glazing — and the narrower gap to triple
The “2–4× double glazing” rule of thumb is worth unpacking, because it sounds worse than it often is in context.
Against standard low-E argon double glazing (centre-of-glass Ug typically around 1.2–1.6 W/m²K), VIG is undeniably a premium product. You are paying more per square metre of glass for a thinner unit that insulates as well or better. If your only goal is to clear Building Regulations, that premium is hard to justify on paper: under Approved Document L in England, replacement windows in an existing dwelling need only reach U ≤ 1.4 W/m²K, or Window Energy Rating band B — a threshold ordinary double glazing already meets, and which VIG clears comfortably. On a like-for-like new-frame basis, plain double glazing wins on cost.
Against triple glazing, the picture shifts. Triple glazing is itself expensive, heavy and thick (often 36–44 mm), and the best tempered VIG matches or beats it on centre-of-glass U-value in a 6–8 mm unit. Compared against triple glazing rather than double, the VIG premium narrows considerably — and in a heritage frame that cannot physically accept a chunky triple-glazed unit, triple glazing is not even on the table. Our vacuum glazing versus double glazing guide walks through where each option genuinely makes sense.
The point is that “how much more than double glazing” is the wrong question in isolation. The right question is what you are comparing VIG against for your windows.
Compared to what? Framing the real alternatives
For most UK buyers, VIG is not competing with a blank sheet of paper. It is competing with two specific alternatives, and its value case is really a comparison against those.
Versus full frame replacement
In a period property, the realistic alternative to retrofitting VIG is often ripping out original timber sashes and fitting entirely new double- or triple-glazed windows. That means new frames, disposal of historic joinery you can never get back, and — in a listed building or conservation area — a much harder consent process, since replacing original windows is exactly what conservation policy tries to prevent. Retrofitting slim VIG into the existing, repaired frames keeps the original joinery and sightlines, and once you price the whole alternative (new frames, plastering, decoration, consents) the VIG route can look competitive rather than extravagant. This “keep the frame” logic is the reason heritage sash and casement retrofit is the dominant UK use case; our guide to vacuum glazing for sash windows covers the joinery side in detail.
Versus secondary glazing
At the other end, secondary glazing — a discreet second frame fitted inside the existing window — is usually cheaper upfront than VIG and is fully reversible, which conservation officers often like. Its trade-offs are different: an extra frame to clean behind, some visual intrusion, and thermal and acoustic performance that depends heavily on the cavity and the product. VIG keeps the single-glazed look and the thin profile, with nothing added inside the reveal. Neither is simply “better” — they optimise for different priorities, and cost is only one axis. Whether the VIG premium earns its place is exactly the question we take on in is vacuum glazing worth it.
Lead times, and why they affect your budget
Lead time is not a price, but it shapes budgets — it dictates scheduling, how long scaffolding or access has to be in place, and whether you can phase the work. Indicative figures reported by UK installers vary noticeably by product:
- Fineo (AGC, made in Belgium and distributed in the UK): roughly 4–8 weeks, the shortest of the mainstream options thanks to European supply.
- LandVac (LandGlass, China): roughly 10–16 weeks, reflecting manufacturing plus sea freight; air freight can shorten this at added cost.
- Pilkington Spacia (NSG, Japan): reported around 16 weeks.
These are indicative installer estimates and will vary with order size, stock and season. The practical lesson is to confirm lead time in writing as part of any quote, especially if the work is tied to scaffolding, a planned decoration schedule or a consent that has its own clock.
Why itemised written quotes matter more here than usual
Because the glass is only part of the job and the joinery scope varies so much between installers, a single headline number tells you very little. An itemised written quote is the only way to compare fairly and to know what you are actually buying. Look for:
- The glass line broken out — product, U-value, whether it is tempered or needs applied safety film, unit sizes, and price per unit or per square metre.
- Joinery and installation as separate lines — survey, frame repairs and rebating, draught-proofing, glazing labour, beads and finishing, and making good.
- Access, removal and disposal — scaffolding, waste, and any specialist heritage requirements.
- Warranty terms in writing. Manufacturer warranties differ (broadly, Spacia around 10 years, LandVac around 15, Fineo around 20). Note that “60-plus year lifespan” figures are manufacturer claims; the warranty is the number you can actually hold someone to, so read what it covers and for how long.
- VAT and lead time, stated explicitly, not assumed.
Get more than one quote, and when totals differ, look at the line items before the bottom line — the gap is usually in how the joinery has been scoped, not in the glass. If a quote is a single lump sum with no breakdown, ask for one; a reputable heritage installer will provide it.
The bottom line
There is no honest way to put one price on vacuum glazing in the UK, and you should be wary of anyone who tries. What we can say with confidence is the shape of it: VIG is a premium product, indicatively a couple to a few times the cost of standard double glazing, with the gap narrowing against triple glazing and often closing entirely once you weigh it against replacing your frames or accept that a heritage window cannot take anything thicker. The figures that circulate — bare units around US$100–300 per square metre globally, Fineo from roughly £120 a unit, LandVac around £290 per square metre — are useful for orientation and useless as commitments, because they price different things at different points in the chain.
Treat every number here as an indicative market estimate, not a quote. Decide first what you are comparing VIG against, get itemised written quotes that separate glass from joinery, and read the warranty rather than the lifespan claim. Do that, and the cost question stops being a mystery and becomes a decision you can actually make. For the wider picture of how the technology works and where it fits, start with our full guide to vacuum insulated glazing.