House Extension Cost in Glasgow: 2026 Price Guide

• Single-storey rear extension (houses): £23,000-£49,500
• Double-storey extension (houses): £49,500-£90,000 upwards

Conventional house extensions in Glasgow are really only relevant outside the tenement core - in areas like Bearsden, Newton Mearns, and the more suburban stretches of the Southside where semi-detached and detached housing predominates. Inside the tenement-dominated inner city, adding space almost always means internal reconfiguration rather than building outward, since flat owners don't own the surrounding land.

Scotland's separate planning system

Scotland's planning and permitted development rules are set under their own legislation, distinct from England's - an English extension guide's specific size limits and rules don't reliably transfer. Always check directly with Glasgow City Council's planning service, and remember that Scottish building control works through a "building warrant" rather than the English "building regulations approval" system.

What drives cost for house extensions here

As with any UK city, access on tighter streets and matching existing materials in a conservation area (Glasgow has several, including parts of the West End around Hyndland and Dowanhill) both push costs up - worth confirming your property's specific status before finalising a design.