Conservatory vs. Orangery: Which is Best for Your Home Extension? 

The photographs rarely settle this. You look at a conservatory and an orangery extension side by side online and they can appear almost identical, or worlds apart, depending on which examples you land on. The real difference is structural, not stylistic, and once you understand the structure, the right choice for your home usually becomes obvious.

We install both types across Surrey and Hampshire, and we survey the property before recommending either. The answer is not in the brochure. It is in how the space needs to work, what the house looks like from the street, and what your planning situation allows. Browse our conservatories and orangeries range to see the options, but what follows is the decision framework we actually use at survey stage.

The Structural Difference Between a Conservatory and an Orangery

The starting point is the glass-to-solid ratio. According to Ultraframe's definition of the conservatory and orangery difference, a conservatory has a roof that is at least 75% glazed and walls that are at least 50% glazed. An orangery extension inverts that: the roof is mostly solid, with a glazed lantern at the centre, and the walls include substantial brick pillars between large windows.

The roof is where the difference matters most. A conservatory roof is predominantly glass or polycarbonate on a pitched frame. An orangery roof has a solid perimeter, often with a flat parapet detail, and the glazed lantern sits centrally over the space. That lantern is not a style choice. It changes how light enters the room, how heat moves through the ceiling, and how the structure meets your existing eaves. Get the roof wrong and you will know about it every January and every July.

The comparison below sets out the key differences at a glance.

One thing worth saying plainly: the line between a well-specified modern conservatory and a standard orangery has become genuinely blurred. Some conservatories now use hybrid roofs with solid insulated panels alongside glazing. Some orangeries use full-height windows that reduce the brickwork considerably. What matters is the glass-to-solid ratio and what is actually built, not what it says on the quote. We raise this at every survey because we have seen too many homeowners choose based on the label rather than the specification.

Year-Round Use: the Honest Thermal Picture

Year-round comfort is the most common reason homeowners choose an orangery extension over a conservatory, and it is a legitimate reason. But the honest picture is a little more complicated than "orangeries are warm and conservatories are cold."

An orangery's solid walls and perimeter roof reduce heat loss compared to a fully glazed conservatory. The lantern brings in daylight without the solar gain problem that comes from a glass roof in July. Across the homes we have surveyed in Surrey and Hampshire, the orangeries that perform best are the ones where the insulation is properly detailed in the walls and the roof lantern, not just assumed. A well-built orangery with that level of care should behave like the rest of your house for most of the year.

A conservatory can be made comfortable all year round, but it takes more investment in specification to get there. Solar-control glazing, a well-insulated roof, and a sensible heating arrangement are all needed. Once you start specifying to that level, the cost gap between a high-spec conservatory and a standard orangery starts to close. That is not a reason to rule out the conservatory route. But it is worth knowing before you commit to a lower-specification structure expecting year-round performance it has not been built to deliver.

Planning Permission and Building Regulations: the Key Difference

Most comparison articles get to planning and then stop. This is where the two structures actually diverge in ways that matter to your project.

For planning permission, both are treated the same way. As confirmed by Planning Portal's permitted development guidance, adding a conservatory or an orangery extension to your house falls within the same set of planning rules as any other home extension. Both can usually be built under permitted development rights without a planning application, provided they stay within size and position limits. For a semi-detached property, that means no more than 3m from the rear wall. For a detached property, no more than 4m. Single-storey, not covering more than half the garden, not extending beyond the front elevation.

Building regulations are a different matter. This is where the structures behave differently, and where we find that homeowners are most often caught out by advice that was not complete.

According to Planning Portal's building regulations guidance for conservatories, conservatories are normally exempt from building regulations when they are built at ground level, are under 30 square metres, are separated from the house by external-quality walls or doors, and are served by an independent heating system. The logic is straightforward: a thermally separated conservatory is not, in building regulation terms, part of the home's heated envelope.

An orangery extension almost never qualifies for this exemption. Most orangeries are open-plan into the main house. That connection means the orangery extension becomes part of your heated space, and building regulations approval is required. The Planning Portal is clear that any new structural opening between a conservatory or orangery and the existing house requires building regulations approval regardless of the structure's exempt status.

Building regulations approval is not a problem. It is a process, and we manage it as part of every orangery extension project. What is a problem is finding out mid-build that it was needed and was not planned for. We flag all building control requirements at survey stage, before you have committed to anything. If an installer has not raised it by the time you receive a quote, ask.

Cost: What Actually Drives the Difference

An orangery extension costs more than a conservatory in most cases. The reasons are structural rather than arbitrary. More brickwork means heavier foundations and more skilled labour. The flat perimeter roof and roof lantern add complexity that a standard pitched conservatory roof does not have. Building control fees are part of the project cost for most orangeries, where they may not be for a conservatory that qualifies for the building regulations exemption.

The orangery price is higher, but the price gap is real, not fixed by category. A high-specification conservatory with a solid or hybrid roof, solar-control glazing, underfloor heating, and proper foundations can approach orangery costs. At that point the question changes. It is no longer "conservatory or orangery at this budget." It becomes: what does this space actually need to do, and which structure answers that most honestly? The specification, not the category name, is what you should be comparing.

The question we ask at survey is simpler than homeowners expect: how are you planning to use this room, and for how long? Those answers shape the specification, and the specification determines the cost. A quote issued without a survey is a number we would almost certainly need to revise once we have seen the property. The same is true across the industry. Anyone quoting without visiting the site is guessing at the details that actually drive the price.

Which Orangery Extension or Conservatory Suits Your Property

For most Surrey and Hampshire semi-detached and detached properties, an orangery extension is the stronger choice for a room you intend to live in. Take a typical Victorian or Edwardian semi in Farnham or Guildford: the brickwork, the period roofline, the proportions of the rear elevation. An orangery extension with matching brick pillars and a flat parapet roof reads as if it was always there. A conservatory with a pitched glass roof announces itself against that setting.

A conservatory is not the wrong answer. For a garden-facing room where maximum light is the priority, or for a lean-to addition on a modern property where the aesthetic suits full glazing, a well-specified conservatory can be exactly right. It costs less. It is often simpler to build. And if the specification is honest about what it can deliver, it will deliver it. Choosing between an extension vs conservatory comes down to how the space needs to function and how it reads against the house.

If your property is in a conservation area in Surrey or Hampshire, or if there is any possibility of an Article 4 Direction removing your permitted development rights, check with the local planning authority before you order anything. We complete that check at every survey. It takes ten minutes and means the planning position is clear before any design commitment is made. You can see examples of our Surrey and Hampshire work on our Surrey orangery installations page.

Three questions worth taking to any survey:

First: what glazing specification do you recommend for year-round comfort, and what is the U-value? Second: does this structure need building regulations approval, and is that included in your quote? Third: are there any Article 4 Directions or conservation area restrictions that affect the design?

A surveyor who cannot answer all three before you commit is not the right person for a project like this.

Frequently Asked Questions

Can you use a conservatory all year round?

Yes, a conservatory can be used all year round, but only if the specification supports it. A standard conservatory with a polycarbonate or basic glass roof will be uncomfortable in winter and often too hot in summer. A well-specified conservatory with solar-control glazing, a solid or hybrid roof, and a properly managed heating arrangement can perform well across the seasons. The label "conservatory" does not tell you what specification you are getting. Ask about the glazing U-value and roof construction before assuming year-round comfort.

Does an orangery add more value to a house than a conservatory?

Generally yes, because orangeries read more like permanent rooms and are assessed more like extensions by surveyors and estate agents. An orangery that is well integrated with the house in terms of brickwork, roof line, and internal finish can add meaningful value. A conservatory can add value too, but buyers are more likely to view it as a seasonal space. The value added by either structure depends significantly on execution and how well it matches the property. A poorly integrated orangery that jars with the frontage adds less value than the cost of building it.

What is the difference between a glass room and an orangery?

"Glass room" is a marketing term used by some suppliers to describe modular glazed structures that sit somewhere between a conservatory and a garden room. The term has no precise definition, unlike conservatory and orangery, which are distinguished by their glass-to-solid ratios. An orangery specifically implies the brick-pillar construction with a solid perimeter roof and a central glazed lantern. When speaking to any installer, ask about the actual glazing percentage and roof construction rather than relying on the name. That answer tells you more than the label does.

Do I need planning permission for an orangery extension in Surrey?

In most cases, no. A rear orangery extension that stays within permitted development limits does not need a planning application. For a semi-detached property in Surrey, that means no more than 3m extension from the rear wall. For a detached property, no more than 4m. The orangery must be single-storey and must not cover more than 50% of the garden. However, Surrey has several conservation areas and properties subject to Article 4 Directions that remove permitted development rights. Always check with the relevant local planning authority or ask your installer to check before ordering. Building regulations approval is a separate requirement and almost always applies to orangeries.

Is an orangery considered an extension for building regulations?

Yes. Because most orangeries connect open-plan to the main house, they do not qualify for the conservatory building regulations exemption that applies to thermally separated structures under 30 square metres. This means an orangery will need a building control application, inspection during construction, and a completion certificate at the end. This is a routine process and most established installers manage it as part of the project. Building regulations approval should be included in the project scope and costed from the outset. If an installer does not mention it, ask explicitly.