In 40 seconds
An orangery is a hybrid room — solid brick piers and a flat perimeter roof with a central glazed roof lantern — sitting between a conservatory and a full extension in both cost and feel. It typically costs £20,000–£40,000 in 2026, more than a conservatory but usually less than a full brick extension. Because it has more solid wall and a flat roof section, an orangery feels more like a permanent room than a conservatory. Like a conservatory it is often classed as permitted development if it stays within size limits, but building regulations may apply depending on the glazing ratio and whether it is separated from the house by external-quality doors. The glazing should be installed by an orangery specialist who is FENSA or CERTASS registered, with building regulations and your local Building Control covering the structure. See how it stacks up against a conservatory and a full extension.