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    Garden Room vs Extension: Which Is Better?

    Garden rooms cost £1,550–£2,450/m² fully installed; brick extensions run £2,500–£4,500/m² before VAT. Garden rooms win on speed, cost and minimal disruption — extensions win on long-term resale value and integrated indoor space.

    Cost comparison

    A 20m² garden room: £30,600 – £49,200 all-in. A 20m² single-storey extension: £50,000–£90,000. Both attract VAT, but extensions also require structural changes to the existing house and party-wall agreements.

    Build time & disruption

    Garden rooms: 4–10 weeks, no disruption to the house. Extensions: 4–8 months, kitchen/wall demolition, dust and party-wall agreements.

    Planning & regulations

    Garden rooms under 30m² usually fall under permitted development. Extensions almost always need planning permission and full building regulations sign-off.

    FAQs

    Which adds more value to a property?

    Extensions add more long-term value (10–20% uplift). Garden rooms add 5–10% but at a fraction of the cost and time.

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