House Extension Cost in Bristol: 2026 Price Guide

• Side return infill: £18,000-£29,500
• Single-storey rear extension: £25,500-£56,000
• Double-storey extension: £56,000-£101,000 upwards

Two different reasons Bristol extensions cost more

Bristol's hillside terrain means a meaningful share of extension projects need retaining walls or additional groundwork just to create a level base, particularly around Totterdown and the steeper parts of Clifton and Redland - this is a real, separate cost driver from conservation area restrictions, and the two sometimes overlap on the same project.

Clifton's conservation area, one of the largest and most established in the city, typically requires extensions to match original stone or render detailing and respect protected rooflines - a different set of constraints again from the more standard permitted development rules that apply to Victorian terraces in Bedminster or Southville.

What pushes costs up further

Access on the narrower streets of Montpelier, St Werburghs and Easton remains a recurring factor, much as in any Victorian terraced city - skip and scaffold permits are often required where a street has no realistic space for either.