What a Small Conservatory Costs to Build
The smallest footprint any UK publisher prices is 3m by 3m, and at that size two independent sources four months apart put the floor at exactly the same figure. That is the strongest agreement anywhere in our new-build data, so this page starts there, names the three styles the register prices at that size, and shows where the number stops being defensible. The rate behind it sits in our per square metre price table.
Lean-to · new build · 3m × 3m (9 m²) · installed, inc VAT
£8,000 to £13,000 typically £10,000
Reasonably evidenced2 sources · identical floor, 1.08× on the ceiling · typical is derived as the midpoint of the two overlapping bands · dated July 2026 and April 2026 · checked 20 August 2026
How much do small conservatories cost?
A small conservatory costs £8,000 to £13,000 installed and including VAT for a uPVC lean-to at 3m by 3m, typically £10,000. We grade that Reasonably evidenced: two independent UK publishers, one in July 2026 and one in April 2026, put the floor at £8,000 to the pound and disagree by 1.08× at the top. The typical is derived as the midpoint of those two overlapping bands and is labelled derived, not published as a market average. Checked 20 August 2026.
That figure covers the whole structure: frame, glazing, roof, base and groundwork, the dwarf wall where the style carries one, fitting labour and VAT at 20 per cent. It is not a supply-only kit price, and the difference between the two is the single biggest reason two quotes for the same conservatory can look nothing alike. If you want a number against your own footprint rather than ours, you can price your conservatory in six questions.
One thing to be clear about before the tables: small is not a size the market defines. No UK publisher prices anything below 3m by 3m, so 9 m² is the floor of the published data rather than the floor of what can be built. Anyone quoting a 2m by 2m conservatory is quoting from something other than published evidence, and so would we be.
What each style costs at 3m by 3m
Three styles are priced at this size by a UK source, and they are priced at the same size on purpose: comparing a lean-to at 9 m² against an Edwardian at 16 m² is how most published comparisons quietly lie. All figures are whole build, installed, including VAT.
| Style | Low | Typical | High | Evidence | Source and date |
|---|---|---|---|---|---|
| Lean-to | £8,000 | £10,000 | £13,000 | Reasonably | Two UK publishers, Jul 2026 and Apr 2026 |
| Victorian | £9,000 | not published | £13,000 | Thin | One UK publisher, Apr 2026 |
| Edwardian | £10,000 | not published | £14,000 | Thin | One UK publisher, Apr 2026 |
| Gable end, P-shape, T-shape, L-shape | No UK source prices these styles at 9 m² | Gap | none found | ||
| Any style, any size, UK headline | £9,000 | £15,000 | £25,000 | Well | 5 publishers, context row |
Style rows: a national trades directory's lean-to cost guide, July 2026, and a second UK publisher, April 2026. The Victorian and Edwardian rows have one publisher each, so both are graded Thin, which is a statement about the evidence and not about the price. The context row is the whole-market headline from five publishers, Well evidenced, and it is there so you can see how far below the market average a small build sits. Checked 20 August 2026.
Read down that table and the useful finding is how small the style premium is at this size: £2,000 between the cheapest floor and the dearest, on a job where the whole-market band is £16,000 wide. Style matters much more at 12 and 16 m², where the faceted plans start needing materially more frame, and every style is priced at matched sizes on conservatory styles and their prices. For the 9 m² footprint itself, taken as a dimension rather than as a size class, see what a 3m x 3m conservatory costs.
What is in that figure, and what is not
This is the itemisation almost nobody publishes, and on a small build it matters more than on a large one, because the fixed lines are a bigger share of a smaller total.
Inside the £8,000 to £13,000
- uPVC frame and glazing
- The roof, glazed
- Base and groundwork
- Dwarf wall, where the style carries one
- Fitting labour
- VAT at 20 per cent
Outside it, and priced separately
- Internal flooring finish
- Electrics and heating
- Blinds
- Removing an existing structure
- Building control fees where they apply
- Making good to the house wall
The inclusion and exclusion lists are the register's own definition for every new-build row on this page, not a per-publisher list, because no UK source states its own scope consistently. Where a source published ex VAT we gross it up at 20 per cent and flag it. Checked 20 August 2026.
The upgrade that moves this number most is the frame. Aluminium and timber both cost more than uPVC and the premium is published as a percentage rather than as a total, which is set out with the sources at uPVC, aluminium and timber frame prices . The second is whether the price you are given includes fitting at all: what a supply-only figure leaves out, line by line, is on conservatory installation cost.
The per square metre rate does not reconcile at this size
One UK publisher, writing on 28 January 2025, puts a whole conservatory build at £1,500 to £2,000 per square metre all in, installed. That row is single source and graded Thin evidence, and we hold it as a cross-check rather than as an input. Checked 20 August 2026.
Run it against 9 m² and it implies £13,500 to £18,000. Our two-source size-banded band for the same job is £8,000 to £13,000, which works out at £889 to £1,444 per square metre. Those two do not overlap at any point. That arithmetic is derived from figures both publishers state, and we show it rather than smoothing it away.
Our reading, stated as a reading rather than a fact: a published rate per square metre is drawn from bigger and better-specified builds, so applying it to a small footprint over-quotes by something like 1.4× to 1.7×. That is why the register bands by size and never multiplies a rate by your square metres. Per-metre spreads in this niche reach 10× while size-banded totals rarely exceed 2×, and both sides of that comparison, structural-only and all-in, are reconciled on the per square metre page linked at the top of this guide.
The same footprint, priced by a premium national installer
A 3m by 3m conservatory is also sold by national installers with their own manufacturing, and the gap is not small. One of them publishes a 3m by 3m from £27,000, or from £31,000 where an opening is formed into the house. Single source, no date on the page, graded Thin evidence, checked 20 August 2026.
We publish those as their own labelled rows and we never blend that installer into a market average, because they are a different spec tier rather than a data error. Two caveats belong with them. The company behind those prices entered administration on 24 April 2024, so how current that page is, is doubtful. And a from price for a premium build is the beginning of a specification conversation, not a comparable to the £8,000 floor above.
What that 2.6× gap is actually telling you. The same 9 m² footprint carries a published price from £8,000 to £31,000. Almost none of that spread is the floor area. It is glazing specification, frame material, roof type, whether the base already exists and who is fitting it. Which is why a small build is a specification decision far more than a size decision, and why we would rather show you the range than hand you an average.
What moves a small build up or down
In the order the published rows say they matter, not in the order that suits a sales conversation.
- Whether the base already exists. The base and the groundwork are inside every figure on this page, and they are the biggest single source of variance between two quotes for the same room. Where a solid foundation or patio is already there, one publisher records a saving of about £2,000 on the job. Single source, undated, graded Thin, checked 20 August 2026.
- The roof. Glazed roofs are what the bands above are priced with. A tiled roof on the same small footprint is a different product at a different price, and it changes the building control position too, which is the one part of this that is regulation rather than preference.
- The frame material. Published as a premium over uPVC rather than as a total. Aluminium is the better-evidenced of the two premiums and, awkwardly for the sales pitch, it is thermally the worse material of the three.
- Style, but less than you would think at this size. £2,000 separates the cheapest published floor from the dearest at 9 m². At 16 m² the same comparison behaves differently, and one publisher's matrix inverts the usual order entirely.
- What the quote silently leaves out. Flooring, electrics, heating and blinds are outside every figure here. A quote that includes them is not dearer than one that does not; it is a different quote.
Once you know which of those apply to you, you can see what yours would cost against the same rows, with the grade and the source shown beside every band.
Against a small extension, and against not building at all
At 9 m² the honest comparison is not conservatory against conservatory, it is conservatory against a single-storey extension of the same footprint, which is a different job with a different regulation status and a different price. That comparison, with both sets of published figures side by side, is on conservatory or extension.
And if you already own a conservatory, this page is the wrong one. You are not pricing a new build, you are pricing the roof, which is £6,000 to £11,000 against the £8,000 to £13,000 on this page, and by some distance the best-evidenced job in the whole register. Start with our conservatory cost calculator if you want an estimate first, or go straight to conservatory roof quotes if you already know the size.
Price your own footprint
Six questions, about sixty seconds, and an estimate built from the rows above with every grade and source shown.
No phone number until the final step, and no email needed to see an estimate. If we do not hold a defensible figure for your exact style and size, the estimate says so rather than inventing one, which is why four of the eight styles on this page show a gap instead of a number.
Questions people ask first
How much is a small conservatory?
What counts as a small conservatory?
Which small conservatory style is cheapest?
Can you build a conservatory for under £8,000?
Why is a small conservatory dearer per square metre?
Does a small conservatory need planning permission?
Is a small conservatory cheaper than a small extension?
Sources on this page: a national trades directory's lean-to cost guide, July 2026; a UK home improvements publisher's conservatory costs, April 2026; a UK price guide, 28 January 2025, for the per square metre cross-check; three further UK publishers for the whole-market context row; a premium national installer for the premium tier rows, undated. Our method, the grades and what would move a row up a band are set out in our pricing method. Every figure checked 20 August 2026, next check due 20 November 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.