The short answer
An orangery is usually quicker, cheaper and lighter than a full brick extension, while a full extension gives the most fully integrated, solid-roofed space. An orangery typically costs £20,000–£40,000 and keeps a high glazing content with a roof lantern; a single-storey full extension often costs more and takes longer, but blends seamlessly into the house with a standard solid roof. Choose an orangery for light and a faster, lower-cost build; choose a full extension where you want a conventional room indistinguishable from the rest of the house. See is an orangery cheaper than an extension for the cost detail.
When you want more room at the back of the house, the choice often comes down to an orangery or a full single-storey extension. They overlap — both are building projects with foundations, walls and a roof — but they differ in glazing, light, cost, build time and how they read as part of the house. This guide compares them across the factors that matter, so you can decide which fits your home and budget. All figures are typical illustrations rather than quotes.
Orangery vs extension at a glance
- Light Orangery: more · Extension: depends on glazing
- Roof Orangery: flat with lantern · Extension: solid
- Typical cost Orangery often lower
- Build time Orangery usually shorter
- Integration Extension most seamless
- Planning Both often permitted development
Light, feel and integration
The orangery’s appeal is light: large windows, glazed doors and a central roof lantern bring in far more daylight than a typical solid-roofed extension, while the brick piers keep it feeling like a room. A full extension gives a conventional solid roof and can be made indistinguishable from the original house, which suits homeowners who want a seamless additional bedroom, kitchen or living room rather than a glazed garden room. If maximising light and keeping a distinct, characterful space is the priority, the orangery leads; if you want the new room to read as part of the original house, the extension does.
| Aspect | Orangery | Full extension |
|---|---|---|
| Glazing & light | High — lantern plus glazed walls | As designed — usually less |
| Roof | Flat perimeter with lantern | Solid, matching the house |
| Typical cost | £20,000–£40,000 | Often higher |
| Build time | Usually shorter | Usually longer |
| Integration | Distinct garden room | Seamless with the house |
Cost and build time
An orangery is generally the lower-cost and faster option. It typically costs £20,000–£40,000 and, because much of the wall is glazing and the roof is a relatively simple flat structure with a lantern, it usually involves fewer trades and less time on site than a full extension with a conventional roof, internal walls and full integration into the house. A full extension’s cost varies widely with size, specification and complexity, but it commonly exceeds the orangery range. For a direct comparison see is an orangery cheaper than an extension and the orangery cost guide.
Planning and building regulations
Both an orangery and a single-storey rear extension are often permitted development if they stay within size, height and footprint limits, and both can require planning permission — for example beyond those limits, in conservation areas or on listed buildings. Building regulations treat them differently: a full extension is fully covered by building regulations, while an orangery may be exempt or covered depending on its glazing ratio and whether it is separated from the house by external-quality doors. See planning permission and building regulations for an orangery. On resale value, RICS and surveyors note that a well-built, well-integrated addition supports value — see does an orangery add value. These are general pointers, not advice for your specific project.
Compare orangery quotes
The right choice depends on your home, budget and how you want to use the space. Use our service to compare quotes from orangery specialists in your area.
Frequently asked questions
Is an orangery cheaper than an extension?
Usually. An orangery typically costs £20,000–£40,000 and is faster to build than a full single-storey extension, which commonly costs more. The gap narrows on large, high-specification orangeries. See is an orangery cheaper than an extension.
Does an orangery let in more light than an extension?
Typically yes. The roof lantern and glazed walls of an orangery bring in more daylight than a conventional solid-roofed extension, though an extension can be designed with large glazing or rooflights to close the gap.
Which is better for resale, an orangery or an extension?
Both can support value when well built and integrated. A full extension that adds a conventional room can suit buyers looking for usable space, while an orangery adds light and character. The effect varies by property and area and is rarely a direct pound-for-pound return. See does an orangery add value.
Do orangeries and extensions need building regulations?
A full extension is fully covered by building regulations. An orangery may be exempt or covered depending on its glazing ratio and whether it is separated from the house by external-quality doors. See building regulations for an orangery.
Sources & further reading
- Planning Portal — extensions, orangeries and permitted development
- GOV.UK / Building Regulations Approved Documents — standards for extensions and glazed structures
- Glass and Glazing Federation (GGF) — consumer guidance on orangeries and glazing
- RICS — home improvements and their effect on property value
This is general information, not advice for your specific property or build. Costs, timescales and outcomes vary with your home, the design you choose and your chosen specialist. We are an independent information and introduction service, not an installer.