An orangery is what the conservatory grew up into. Where a conservatory is a glass box bolted to the house, an orangery is a real room: masonry corners and piers matched to the house, full-height glazing between them, and a flat insulated roof perimeter framing a roof lantern that pours daylight into the middle of the plan. The Extension Company designs and builds them across London and Hertfordshire from our Cockfosters base, at the specification the finest houses in London expect.
Orangery, conservatory or extension: which do you actually want?
- Conservatory: mostly glass, cheapest to build, hardest to heat and cool. Right for some budgets; rarely right for a premium house.
- Orangery: solid structure with generous glazing and a lantern. Reads as part of the house, performs like a proper room, and suits period and high-value properties where a glass lean-to would look wrong.
- Glazed rear extension: fully solid roof with slim-framed sliding glazing. The most seamless option for open-plan kitchen living.
The honest test: if you want a garden-facing room that feels architectural and works year round, and your house deserves brick detailing rather than uPVC, the orangery is the answer. If you want the whole back of the house opened into one kitchen-living space, you likely want a glazed rear extension or a bigger programme from our luxury extensions range.
What an orangery costs in 2026
Realistic all-in build ranges for London and Hertfordshire, excluding VAT, professional fees and any kitchen fit-out:
| Scope | What it is | Typical cost |
|---|---|---|
| Classic orangery | Brick piers, lantern roof, French or sliding doors, ~20 to 30m² | £60,000 to £95,000 |
| Large orangery | Wider spans, structural glazing between piers, ~30 to 45m² | £85,000 to £130,000 |
| Orangery within a bigger programme | Part of a wrap-around or whole-house scheme | Priced on design |
The swing factors are the glazing specification, the lantern size, and how far the detailing goes: stone cills, handmade brick and hardwood joinery all push toward the top of the band and all belong on the houses we build for. As everywhere on this site, the quote is fixed and itemised, and the signed figure is the paid figure.
Planning: often simpler than people expect
Because an orangery is usually a single-storey rear addition, many fall under permitted development: up to 4m deep on a detached house without any application, and up to 8m with larger-home prior approval. We still secure a Lawful Development Certificate so the consent is documented when you sell. Conservation areas, listed houses, green belt plots and estate covenants change the route, sometimes to full application, and since much of our patch carries exactly those layers we map them at the first visit. Building regulations apply either way, thermal performance included, and we design the glazing-to-solid ratio so the room passes properly rather than on a technicality.
Built like the house, not bolted to it
The difference between a fine orangery and a regrettable one is detail: brick coursing and mortar matched to the original, lantern flashings in lead done the traditional way, cills and copings that line through with the house, and doors hung so they still glide in a decade. That is build-quality territory, which is why our orangeries go through the same fixed-price, one-project-lead process as every extension we deliver.