The Reconciled Cost per Square Metre for a UK Conservatory
Three published UK rates answer this question and none of them is measuring the same job. One prices the whole build, one prices the structure alone, one prices a replacement roof. Set side by side they run from £460 to £2,000 per square metre, and the only way to use any of them is to know which job it counts.
New build · whole job, all in · per m² · installed
£1,500 to £2,000 per square metre
Thin evidence1 source · 1.33× · dated 28 January 2025 · checked 20 August 2026
How much does a conservatory cost per square metre?
A UK conservatory costs £1,500 to £2,000 per square metre for the whole job, installed. We grade that Thin evidence: one publisher, dated 28 January 2025, spread 1.33×, with no second source anywhere in our register to corroborate it. Checked 20 August 2026.
That is the honest headline, and the next sentence matters more than the figure. A per square metre rate is the least reliable way to price a conservatory, and we publish it as a cross-check on the size-banded totals rather than as the number to budget from. The reason is arithmetic rather than opinion: the published totals for a given size and style rarely disagree by more than 2×, while the published rates for a square metre of conservatory disagree by more than 4× before you take out the two figures we exclude. If you want a number for your own build, work out what your conservatory will cost from the size-banded evidence instead.
None of the three rates on this page carries a stated VAT position in our register, so we do not assert one. Where a size-banded total on this site is described as including VAT, that is because the source said so. Where a rate is silent, we leave it silent rather than gross it up and present the result as published.
Three rates, three different jobs
The spread between these rows is not a measurement error. It is three publishers counting three different scopes of work and labelling all of them per square metre.
| What the rate counts | Rate per m² | Evidence | Source and date |
|---|---|---|---|
| Whole build, all in, installed | £1,500 to £2,000 | Thin1 source, 1.33× | A UK price guide, 28 January 2025 |
| Structure only, by style, excluding base, floor and fitting | £875 to £1,050 | Thin1 source, 1.20× | A national trades directory, 24 June 2026 |
| Replacement tiled roof only, installed | £460 to £900 | Reasonably evidenced3 sources, 1.96× | Three UK publishers, 2026 |
The structural-only row is the one with the most detail behind it. The same source prices four styles separately at the same scope: a lean-to with a polycarbonate roof and a dwarf wall at £1,000, a fully glazed lean-to at £970, an Edwardian with polycarbonate and a dwarf wall at £875, and a Victorian with a glass roof and a dwarf wall at £1,050. Those four sit inside 1.20× of each other, which is the tightest per square metre agreement anywhere in our data, and it is agreement within one publisher rather than between publishers. That is why it stays graded Thin. The frame material is a further variable behind the first two rows, and conservatory frame materials and prices sets out what that choice adds.
The roof row is a different job again and belongs to the roof cluster rather than to a new build. It is here because it is the only per square metre rate on the site with three independent publishers behind it, and because it is the rate most often quoted back at us as if it priced a conservatory.
The cross-check nobody publishes
Every publisher in this niche prints a per square metre rate somewhere and a size-banded price table somewhere else. As far as our survey found, none of them multiplies the first by a floor area and checks whether it lands on the second. We did.
| Size | Rate implies | Register says | Result |
|---|---|---|---|
| 3m × 3m (9 m²), lean-to | £13,500 to £18,000 | £8,000 to £13,000 | Rate floor is above the register ceiling |
| 4m × 3m (12 m²), lean-to, glazed | £18,000 to £24,000 | £9,000 to £14,000 | No overlap at all |
| 4m × 4m (16 m²), Edwardian | £24,000 to £32,000 | £13,300 to £17,100 | No overlap at all |
| 15 to 20 m², P-shape | £22,500 to £40,000 | £13,250 to £19,700 | No overlap, against our best-evidenced row |
The all-in rate over-predicts the size-banded totals at every size our register holds. At 9 m² the two bands miss each other by £500. By 16 m² the rate is implying roughly £10,000 more than the totals do, and at the P-shape row it is implying roughly double. That last line is the one that settles it: the P-shape band is our only Well evidenced new-build figure, four independent publishers inside 1.18×, and the rate does not come close to it.
We are not calling the rate wrong. A single 2025 figure cannot be tested against a register it was never fitted to, and the publisher may well be counting a specification the size-banded sources are not. What we can say is that anyone multiplying £1,500 to £2,000 by their floor area is going to arrive at a number the published totals do not support, which is a good reason to price from conservatory styles and what each one costs and from what a small conservatory costs instead.
What the structural-only rate reveals
Run the same test on the rate that explicitly excludes the base, the floor and the fitting, and it behaves better than the rate that claims to include them.
| Size | Rate implies | Register says | Result |
|---|---|---|---|
| 3m × 3m (9 m²), lean-to | £7,875 to £9,450 | £8,000 to £13,000 | Lands on the register floor |
| 4m × 4m (16 m²), Edwardian | £14,000 to £16,800 | £13,300 to £17,100 | Sits inside the band |
| 5m × 4m (20 m²), Victorian | £17,500 to £21,000 | £18,000 to £25,000 | Lands on the register floor |
A rate that leaves out the base, the floor and the labour predicts the installed totals more closely than a rate that says it includes everything. Read one way that is a curiosity about two publishers. Read the other way it is the most useful thing on this page: the gap between £875 to £1,050 for the structure and £1,500 to £2,000 for the whole job is the clearest published evidence we have found of how much of a conservatory price is not the conservatory. On those two figures, somewhere between a third and a half of what you pay is groundwork, fitting days and everything else that is not frame and glass.
That is the split worth understanding before you compare two quotes, and it is set out in full in conservatory installation cost.
The figures we excluded, and why
Two published per square metre figures are not in the table above, and leaving them out silently would make the spread look tidier than it is.
The first is a national trades directory's own on-page job estimator, which returns £195 per square metre for a roof replacement while the body copy on the same site quotes roughly £750. That is a 3.8× contradiction inside one publisher and it reads as a live data fault rather than a market position, so we neither blend it nor cite it as a price.
The second is a trades marketplace quoting £50 to £100 per square metre under a roof heading. That is roughly ten times below every other publisher, and the most likely reading is that it prices tile material alone rather than an installed roof. Included, it would drag the published range to £50 to £2,000, which is 40× and tells you nothing.
Both are recorded in the register with those reasons attached, because an excluded figure with a published reason is evidence and an excluded figure with no reason is just a tidier table. The full method sits in our costing method and sources, and every figure on this site traces back through the sources behind every figure.
Price it against the size bands, not the rate
Our calculator runs on the size-banded totals for exactly the reason this page sets out. Where we do not hold a defensible figure for a style and size, it says so rather than multiplying a rate to fill the gap.
Check what your conservatory will cost
If the job is a replacement roof rather than a new build, comparing conservatory roof quotes from installers who cover your postcode is the faster route, and use the Conservatory Cost Calculator first so you know the published band before the first visit.
Questions people ask first
How much is a conservatory per square metre?
Why do per square metre conservatory prices vary so much?
Is a per square metre rate a reliable way to budget?
What does a conservatory cost per square foot?
Does the rate include VAT?
Is a bigger conservatory cheaper per square metre?
Sources on this page: a UK price guide, 28 January 2025, for the all-in rate; a national trades directory, 24 June 2026, for the structure-only rates by style; three UK publishers dated 2026 for the replacement roof rate; and the size-banded totals in our own register, drawn from a national trades directory (July 2026), a UK home improvements publisher (April 2026) and the further publishers named on each size page. Two figures are excluded with reasons published above. Every figure checked 20 August 2026.
Find out what yours costs
Six questions, about sixty seconds, and an estimate built from published UK figures with every source shown. Then up to four local installers can quote you, if you want them to.