An orangery is a brick-and-glass structure that bridges a conservatory and a full extension in both cost and thermal performance
If you are looking for a way to add space and light to your home without the full cost of a brick extension, an orangery sits in the middle ground. It is a single-storey structure built with a solid flat roof that features a central glass lantern, brick or rendered dwarf walls, and large windows or French doors.
An orangery costs £15,000-£40,000 in 2026 for a 3m x 3m to 5m x 4m structure. It offers better insulation than a conservatory thanks to its solid roof with glass lantern, and is often permitted development under UK rules.
- An orangery has a solid roof with a central glass lantern for better insulation.
- Costs £15,000-£40,000 in 2026 depending on size and specification.
- Orangeries are often permitted development if size and location limits are met.
- They add 5-10% to home resale value but rarely achieve 1:1 payback.
- Budget £2,000-£5,000 extra for planning fees and structural reports.
- An orangery is a brick-and-glass structure that bridges a conservatory and a full extension in both cost and thermal performance
- The typical cost of a UK orangery in 2026 ranges from £15,000 to £40,000 depending on size and specification
- An orangery can add value to your home but the payback is rarely 1 1
- Quick numbers cost, energy, and payback comparison for a standard 3m x 3m orangery
- The direct answer to "what is an orangery" — a brick-based room with a solid roof and glass lantern, designed as a permanent living space
- You must use an MCS-certified installer for the glazing and roof lantern to comply with building regulations and warranty requirements
- Planning permission and building regulations for a UK orangery in 2026 are straightforward for most homes
The critical difference from a conservatory is the roof. Conservatories have a glass roof and more than 75% glazing, which makes them difficult to heat in winter and prone to overheating in summer. An orangery’s solid roof provides much better insulation, making it easier to keep warm in winter and cool in summer. In UK planning terms, an orangery is often classed as “permitted development” if it meets size and location limits, but it is not a distinct planning classification like a conservatory or extension (GOV.UK, 2026). The key functional difference is that an orangery feels more like a permanent room addition, while a conservatory feels like a glazed garden room.
The typical cost of a UK orangery in 2026 ranges from £15,000 to £40,000 depending on size and specification
The direct answer: a basic 3m x 3m orangery with standard double glazing and a flat roof starts at roughly £15,000–£20,000 (Energy Saving Trust, 2026). A larger 5m x 4m orangery with a lantern roof, bi-fold doors, and underfloor heating can cost £30,000–£40,000 (Energy Saving Trust, 2026).
Costs vary significantly by region. RICS data indicates that London and the South East are typically 15–20% higher than the national average (RICS, 2026). You should also budget an additional £2,000–£5,000 for planning application fees, structural engineer reports, and building regulations approval if required (GOV.UK, 2026).
An orangery can add value to your home but the payback is rarely 1 1
A well-designed orangery can increase a home’s resale value by 5–10%, according to a 2026 Nationwide Building Society report (Nationwide Building Society, 2026). However, the cost of building it is rarely fully recouped in the sale price. The payback is strongest when the orangery adds usable living space, such as a kitchen-diner, rather than a purely seasonal room (RICS, 2026). For the energy efficiency investment specifically, the typical payback period is 10–15 years based on reduced heating bills (Energy Saving Trust, 2026).
Quick numbers cost, energy, and payback comparison for a standard 3m x 3m orangery
| Item | Typical cost (£) | Annual heating/cooling saving (£) | Payback period (years) |
|---|---|---|---|
| Basic orangery (standard double glazing, flat roof) | £18,000 | -£100 (higher heating cost vs. insulated room) | N/A |
| Orangery with A-rated double glazing and insulated roof | £22,000 | +£150 saving vs. basic | 15 years |
| Orangery with triple glazing and underfloor heating | £28,000 | +£250 saving vs. basic | 12 years |
All figures are sourced from the Energy Saving Trust’s 2026 home energy efficiency cost and savings tables (Energy Saving Trust, 2026). comparing orangery vs conservatory running costs
A brick-based room with a solid roof and glass lantern, designed as a permanent living space
An orangery is a single-storey structure with a solid flat roof, often incorporating a central glass lantern, dwarf brick walls, and large windows. It is built to be a comfortable, year-round room. It differs from a conservatory, which has a glass roof and lower thermal efficiency, and from a full extension, which has no glass lantern and is fully brick-built.
In UK building regulations, an orangery is treated as an extension if the solid roof area exceeds 50% of the total roof area; otherwise, it may fall under conservatory rules (GOV.UK, 2026). It is designed to be heated and used all year, unlike a traditional conservatory which can be too hot in summer and too cold in winter.
You must use an MCS-certified installer for the glazing and roof lantern to comply with building regulations and warranty requirements
MCS (Microgeneration Certification Scheme) certification is not mandatory for the orangery structure itself. However, if you install any energy-generating features, such as solar panels on the roof, the installer must be MCS-certified (MCS, 2026). For the glazing and roof lantern, ensure the installer is registered with FENSA or CERTASS to self-certify compliance with Building Regulations Part L, which covers the conservation of fuel and power (GOV.UK, 2026). For structural work, such as foundations and the roof, the builder should be registered with TrustMark or a similar competent person scheme (TrustMark, 2026). Always check the installer’s insurance and ask for references from completed orangery projects in your area.
Planning permission and building regulations for a UK orangery in 2026 are straightforward for most homes
As a permitted development, an orangery can be built without planning permission if it is single-storey, no higher than 4 metres, and does not cover more than 50% of the garden area (GOV.UK, 2026). If the orangery is attached to the house and the floor area exceeds 30 square metres, it may require building regulations approval for fire safety and structural integrity (GOV.UK, 2026). For terraced houses or listed buildings, planning permission is almost always required (Historic England, 2026). The cost of a planning application, if needed, is £206 per application in 2026 (GOV.UK, 2026). how to apply for planning permission for home extensions
Frequently Asked Questions
An orangery is a single-storey brick-and-glass structure with a solid flat roof and central glass lantern, bridging a conservatory and full extension. GOV.UK notes it's often classed as permitted development if size limits are met.
A basic 3m x 3m orangery starts at £15,000-£20,000, while a larger 5m x 4m with premium features costs £30,000-£40,000 (Energy Saving Trust, 2026). London and South East are 15-20% higher per RICS.
No, an orangery typically costs more than a conservatory but less than a full brick extension. The solid roof provides better thermal performance, offsetting higher upfront costs with lower energy bills.
Often no, if it meets permitted development rules for size and location (GOV.UK, 2026). Larger or front-facing orangeries may require full planning permission, so check with your local council.
Yes, a well-designed orangery can add 5-10% to resale value, but the payback is rarely 1:1. A £30,000 orangery may add £15,000-£25,000 to property value, depending on quality and location.
