Short answer: UK cost guides published in 2026 put a typical fitted conservatory at roughly £9,000 to £25,000. A small lean-to can start from around £5,000 to £12,000, a Victorian or Edwardian of about 3 to 4 metres square usually costs £10,000 to £18,000, and larger P-shaped or T-shaped designs often reach £15,000 to £25,000 or more. Solid or tiled roofs, aluminium frames and a lot of groundwork push the figure higher. These are market guides from the named sources below, not Inspired Glazing prices. Your own price will depend on a survey.
For an overview of the styles, frames and glass we offer around Windsor, Maidenhead and the wider South East, see our main conservatories page. This guide is all about the money.
Conservatory prices by style
We checked four UK cost guides in October 2026. They don’t use the same sizes, and some quote the structure only, so we’ve noted what each figure covers.
Lean-to
- Checkatrade (2026, 3.5 × 3.5 m): £9,000 to £11,500 in UPVC.
- ExpertSure (verified October 2026): from about £5,000 for a 10 m² UPVC lean-to with a polycarbonate roof, or £9,000 to £13,200 with a glass roof.
- MyJobQuote (September 2026, 3 × 3 m on a dwarf wall): about £12,000 fully fitted, or £9,750 for the structure alone.
More on this style: lean-to conservatories.
Victorian
- Checkatrade (3.5 × 3.5 m): £12,000 to £13,500 in UPVC.
- ExpertSure (15 m², UPVC, glass roof): £10,000 to £18,000, rising above £20,000 with a tiled roof.
- MyJobQuote (3 × 3 m): about £13,500 fully fitted.
More: Victorian conservatories.
Edwardian
- Checkatrade (3.5 × 3.5 m): £10,500 to £12,000 in UPVC.
- ExpertSure (15 m², UPVC, polycarbonate roof): £9,000 to £15,000, up to about £17,000 with a glass roof or aluminium.
- MyJobQuote (3 × 3 m): about £13,500 fully fitted.
More: Edwardian conservatories.
P-shaped, L-shaped and T-shaped
- P-shaped: ExpertSure gives £15,000 to £25,000 for about 20 m². MyJobQuote gives £13,500 to £16,500 for the structure alone at 15 to 20 m².
- T-shaped: MyJobQuote gives £13,000 to £13,500 for a 5 × 3 m structure and £17,000 to £18,000 for 5 × 4 m, before the base and installation.
- L-shaped: none of the guides we checked publish a separate L-shaped figure. Because an L-shape wraps around a corner of the house, it involves more roof junctions and often more groundwork than a simple rectangle of the same floor area, so budget at least in line with P and T-shaped figures.
More: P-shaped, L-shaped and T-shaped conservatories.
Where the sources disagree: a lean-to ranges from “from £5,000” (ExpertSure) to about £12,000 fully fitted (MyJobQuote). Much of the gap is what’s included. MyJobQuote says the base, groundwork and installation add from £2,500 on top of structure-only prices, while ExpertSure’s lowest figure assumes a small room with a polycarbonate roof. When you compare quotes, check that each includes the base, dwarf walls, roof, glazing, electrics, flooring preparation and VAT.
Prices by size
ExpertSure gives about £8,000 to £15,000 installed for a 3 × 3 m conservatory and £15,000 to £30,000 or more for 6 × 4 m. It estimates each extra square metre adds roughly £300 to £600. MyJobQuote’s per-square-metre structure costs are higher, at about £810 to £1,050 depending on style and roof. Again the sources diverge, largely because the per-metre cost falls as rooms get bigger: foundations, wall-to-house junctions and doors cost much the same whatever the size.
How the roof changes the price
- Polycarbonate: the cheapest option. ExpertSure gives £2,000 to £4,000 fitted for about 10 m². It is noisier in rain and less effective against heat and glare. The Eco Experts (prices dated February 2025) goes further and says it is “not recommended” because it degrades quickly.
- Glass: ExpertSure puts a 15 m² glass roof at about £4,000 to £8,000. Self-cleaning, solar-control or low-E glass adds cost but makes the room much more comfortable year round.
- Solid or tiled: ExpertSure gives £6,000 to £15,000 for about 15 m², plus £1,000 to £3,000 if the frame needs structural strengthening. A solid roof keeps the room warmer in winter and cooler in summer, but LABC guidance says that significantly reducing the glazing or translucence of the roof means the structure “can no longer be considered exempt”, so the new roof must meet the Building Regulations (LABC guide, via Test Valley Borough Council). Allow for building control fees.
Roof lanterns are another way to bring light into an extension with a flat roof. See roof lanterns and skylights, and our orangeries page if you’re weighing up a more solid structure.
Replacing just the roof
If your existing conservatory is too hot in summer and too cold in winter, a new roof can be much cheaper than starting again. Checkatrade puts the average roof replacement at about £10,000. ExpertSure gives £4,500 to £10,000 for a new glass roof and £8,000 to £18,000 for a tiled warm roof. Our replacement conservatory roofs page explains the options.
Frame material
ExpertSure puts basic white UPVC frames at about £150 to £250 per linear metre and aluminium at £300 to £500. The Eco Experts says aluminium typically adds about 25% over UPVC. Aluminium gives slimmer sightlines and more colour choices, and it holds its colour well. We don’t build timber conservatories. If you like the look of wood, ask us about woodgrain-finish frames, and we will confirm which finishes are available for your design.
Planning and Building Regulations costs
Many conservatories don’t need a planning application, but you should budget for checks. For the full rules, see our planning permission for conservatories and porches guide.
- Householder planning application: £548 in England from 1 April 2026 (North Yorkshire Council fee schedule, which applies the national fees).
- Prior approval for a larger rear extension: £249 from the same date.
- Lawful Development Certificate: half the normal planning fee. It is optional, but it gives you written confirmation that the work is permitted development, which helps when you sell.
- Drawings: ExpertSure suggests £500 to £1,500 if you need architectural drawings for an application.
- Building Regulations: a conservatory is normally exempt if it is at ground level, under 30 m², single storey, separated from the house by external-quality walls, doors or windows, has independent heating controls, and its glazing and fixed electrics comply (Planning Portal). Any new structural opening between the house and the conservatory still needs approval, and building control fees vary by council.
Extras people forget to budget for
- Moving drains, manholes or downpipes where the base will go.
- Electrics, sockets and lighting, plus heating that can be controlled separately.
- Flooring, and blinds to control glare. Checkatrade puts conservatory blinds at about £2,650 on average. See our blinds page.
- Doors into the garden. French doors or sliding doors change both price and how the room is used.
Ways to keep the cost down without regretting it
- Keep the shape simple. A rectangular lean-to or Edwardian has fewer roof junctions than a Victorian or P-shape of the same floor area.
- Stay within permitted development where you can, so you avoid application fees, drawings and weeks of waiting.
- Re-use a sound base. If you’re replacing an old conservatory, a base and dwarf walls in good condition may be kept. We will check this at survey.
- Spend on the roof glass, not the trimmings. Good solar-control glass makes more difference to how often you use the room than decorative finials or cresting.
Get a conservatory quote you can rely on
We will visit, measure, talk through the style, roof and frame that suit your house, and give you a clear written quote. Every installation carries our 10-year guarantee. Call 01753 965 005 or request your free quote.
Frequently asked questions
How much does a small conservatory cost?
A small lean-to of about 3 × 3 metres typically costs from around £5,000 with a polycarbonate roof to about £12,000 fully fitted with glass, based on ExpertSure, Checkatrade and MyJobQuote figures for 2026. The difference mostly comes from what each guide includes, such as the base, dwarf walls, roof type and installation, so compare like-for-like quotes.
What is the cheapest style of conservatory?
The lean-to is usually the cheapest, because it has a simple rectangular plan and a single-slope roof. Published 2026 guides put lean-tos roughly £1,000 to £2,500 below a Victorian or Edwardian of similar size. A polycarbonate roof is cheaper again, but glass gives better comfort, less rain noise and a longer-lasting finish.
Does a conservatory need planning permission?
Often not. A conservatory is treated as a home extension and can be built under permitted development if it meets limits on depth, height, position and land coverage, and your home is not affected by an Article 4 Direction, planning condition or other restriction. If it exceeds those limits, a householder application costs £548 in England from April 2026.
How much does it cost to replace a conservatory roof?
Checkatrade gives an average of about £10,000. ExpertSure quotes £4,500 to £10,000 for a new glass roof and £8,000 to £18,000 for a tiled warm roof, with extra cost if the frame needs strengthening. Replacing the roof can be much cheaper than replacing the whole conservatory if the base and frames are sound.
Is an aluminium conservatory more expensive than UPVC?
Yes, typically. The Eco Experts says aluminium usually adds about 25% over UPVC, and ExpertSure puts aluminium frames at roughly £300 to £500 per linear metre compared with £150 to £250 for basic white UPVC. Aluminium gives slimmer frames and more colour choice. We can quote both so you can compare.