Is a conservatory cheaper than an extension?

It varies with the design and specification, so get written quotes for both rather than assuming.

Do I need planning permission for a conservatory?

Sometimes. Many are permitted development, but limits apply. Check with your council or the Planning Portal.

Is a conservatory warm enough to use all year?

It depends on the glazing, insulation and heating. Ask your designer how it will perform in winter and summer.

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Conservatory vs extension: which is better for your home?

By the GlowUpp team · 27 October 2026

The plain back of a brick house next to the same house with a new glazed extension

BeforeAfter‹›

An AI-generated example. Real results depend on your own space.

Both add space and light, but they feel and perform very differently. The right choice depends on how you want to use the new room all year round.

What is the difference?

A conservatory is mainly glazed, with glass walls and often a glass roof. An extension is built more like the rest of the house, with solid walls and a conventional or partly glazed roof. Many modern designs sit in between.

Comfort through the seasons

Glass-heavy rooms can be too hot in summer and cold in winter. Extensions with proper insulation are usually comfortable all year. Ask about glazing, roof type and heating.

Use

A conservatory suits a light, informal room such as a sitting area.
An extension suits a kitchen, dining room or living space used every day.

Light and views

Conservatories maximise light. Extensions can still be bright with rooflights and large glazed doors, while keeping more solid wall for storage and furniture.

Rules and permissions

Both may be permitted development or need planning permission, depending on size, position and where you live. Building regulations may apply, though some conservatories are treated differently if certain conditions are met, such as being separated from the house by doors. Check with your council.

Heating and running costs

Ask the designer how the room will be heated and insulated, and how it will perform in winter and summer.

Ask your designer or builder

How will the room be insulated, heated and ventilated?
What permissions are needed?
How will it connect to the existing house?
What guarantee comes with the work?

See the idea

Upload a photo of your house to GlowUpp to see AI-generated ideas, and use them to brief designers. Always ask a qualified professional before moving gas, electrics or plumbing, or changing anything structural, and check your lease or local rules if you rent or live in a conservation area.

See your own extension redesigned

Upload a photo and see AI-generated ideas in about two minutes. Free for homeowners, no sign-up needed to start.

Try it with your photo

Common questions

Is a conservatory cheaper than an extension?: It varies with the design and specification, so get written quotes for both rather than assuming.
Do I need planning permission for a conservatory?: Sometimes. Many are permitted development, but limits apply. Check with your council or the Planning Portal.
Is a conservatory warm enough to use all year?: It depends on the glazing, insulation and heating. Ask your designer how it will perform in winter and summer.