Conservatory vs extension: cost compared
A conservatory is the budget route to extra space: typically about £14,000, versus roughly £40,000 to £64,000 for a 20 m² single-storey extension before fit-out. An extension is fully integrated, better-insulated living space and usually adds more value, while a conservatory is cheaper and quicker but less usable in deep winter unless it has a solid roof.
Conservatory vs House extension: the difference
| Factor | How they compare |
|---|---|
| Typical cost | Conservatory about £14,000 installed; extension about £2,000 to £3,200 per m² (a 20 m² build is about £40,000 to £64,000). |
| Comfort and use | An extension is insulated, year-round living space. A glazed conservatory can be cold in winter and hot in summer unless you add a solid or tiled roof. |
| Value and planning | An extension typically adds more to the property value; conservatories are more often permitted development within size limits. |
| Best for | Conservatory: extra space on a budget, fast. Extension: proper, year-round living space and more added value. |
Common questions
Yes, usually by a wide margin. A typical conservatory is around £14,000 installed, while a single-storey extension of similar floor area is often £40,000 or more before any kitchen or bathroom fit-out.
Generally no. A well-built extension adds insulated, integrated living space that tends to add more value, whereas a basic conservatory adds less, especially if it is not usable all year.
These are independent guide prices based on typical UK jobs in 2026. Your actual cost depends on your property, spec, access and where you live. Always get at least three written quotes before committing.