Conservatory prices are quoted as a single figure for a finished room and built from five quite separate pieces of work, only one of which is the glazing everybody compares. Two quotes for the same size room routinely differ by more than the frames cost, and almost always because they have made different assumptions about the ground, the base and the electrics.
How much is a conservatory UK-wide? The five pieces of the price
Groundworks and the base, which includes excavation, foundations, a damp proof membrane, insulation and a floor slab, and which is invisible in a brochure. The dwarf wall if there is one, in brick to match the house. The frames and glazing. The roof. And the fit out: floor finish, electrics, lighting, heating and any doors into the house. Groundworks is the piece most likely to be assumed rather than surveyed, and the piece most likely to move a price after signature.
How much does it cost to build a conservatory? The ground decides
Foundation depth depends on the ground and on what is near it. Clay soils and nearby trees mean deeper foundations. A drain, an inspection chamber or a manhole in the footprint has to be dealt with properly and sometimes diverted, which needs the water authority's agreement where it is a public sewer. Sloping ground means either stepping the base or building it up. None of this is visible from a size in metres, which is why per square metre figures are a starting point and not a price.
Edwardian conservatory cost, style and size: what they really change
A lean to is the simplest shape and the cheapest per square metre. Victorian and Edwardian styles add facets, corner posts and a more complex roof. An orangery adds masonry piers and a flat perimeter roof, which is closer to an extension. Oak framed construction is a different trade at a different price entirely. Larger rooms cost more in total and usually less per square metre, up to the point where the roof span needs a different structural solution.
Reading a calculator, and the sales pattern
Online calculators and quote tools work from a size and a style against typical rates, which makes them useful for a range and unreliable for a decision, because they cannot see your ground, your drains or your access. This is also a trade with a long established discounting pattern where an opening price falls steeply if you sign immediately. A contract agreed in your home normally carries a statutory cancellation period, whatever the offer says about expiring tonight.
Conservatories prices: what a comparable quote itemises
The base construction and its assumed foundation depth, what happens if the ground requires more, how any drainage in the footprint is dealt with, the dwarf wall and brick specification, frame system and colour, glazing specification for walls and roof separately, the roof type, doors into the house, electrics and heating, floor finish, waste removal, and who certifies whatever is notifiable. Three quotes on that basis are comparable; three headline figures are not.
Questions people ask about average cost of a conservatory UK
Why do conservatory quotes vary so much?
Mostly because of what is assumed below ground and what is included in the fit out. The frames are the most visible and least variable part.
Is the cost of building a conservatory lower than an extension?
Usually per square metre, because the exemption and the lighter construction reduce both cost and process. A solid roofed, fully insulated conservatory converges on extension cost, at which point the comparison is worth making properly.
Do I need planning permission for a conservatory?
Often not on a house within the permitted development limits, which cover size, height and position. Flats, listed buildings and some conservation areas are different, and the limits are specific enough to be worth checking.
Should I trust an online conservatory calculator?
For an order of magnitude only. It cannot see the ground, the drains or the access, which are the three things most likely to change the price.
Can a conservatory be built over a drain?
Building over or near a public sewer needs the water authority's agreement, and an inspection chamber in the footprint has to be dealt with properly. It is a common and solvable problem that belongs in the quote rather than in a variation.