House Extension Cost in Newcastle: 2026 Price Guide
08 Aug 2026
- Single-storey rear extension (houses): £23,000-£49,500
- Double-storey extension (houses): £49,500-£90,000 upwards
Conventional house extensions are most straightforward in Gosforth and similar areas where full Edwardian and interwar houses predominate, rather than the Tyneside flat-split terraces common across Heaton, Byker and much of inner Jesmond, where extending typically involves an agreement with the other flat owner over shared structure, access and any rear yard.
What drives cost
Newcastle City Council's conservation areas, including parts of Jesmond and the Grainger Town area around Grey Street, typically require extensions to match existing materials and rooflines more closely than standard permitted development elsewhere in the city.
Access on terraced streets
As with any terraced city, narrow streets without side access mean materials and spoil go through the property, which builders will price in - worth asking directly whether this is accounted for in a quote.
Ready to get quotes? Post your job on builderfinder.uk and hear from vetted, reviewed builders who cover Newcastle - it's free, and your details stay private until you accept one.
Find a trade in Newcastle
Frequently asked questions
How much does a house extension cost in Newcastle?
A single-storey rear extension for a full house runs £23,000-£49,500, and a double-storey extension £49,500-£90,000 upwards.
Do Tyneside flats and full houses face the same extension rules in Newcastle?
No - conventional extensions are most straightforward in areas like Gosforth where full houses predominate, while Tyneside flats in Heaton, Byker and inner Jesmond typically need agreement with the other flat owner first.
Ready to get started?