Two-storey extensions in Barnsbury
Everything for a two-storey extension in Barnsbury, in one place: types, guide prices for London, the approval rules in England and how to get started.
Barnsbury at a glance
- Postcode districts
- N1C
- Area
- Greater London, England
- Price region
- London
- Nearest towns
- Islington (0.7 miles), King's Cross (0.7 miles), Holloway (0.9 miles), Highbury (1 mile)
- Approvals
- Two-storey rear: up to 3 m deep and 7 m from the rear boundary under permitted development. Side, wraparound and front: planning permission.
We cover postcode district N1C in and around Barnsbury, along with neighbouring Islington, King's Cross and Holloway.
Extensions available in Barnsbury
Two-storey rear extensions
From £67,000 in Barnsbury. Free visit to firm it up.
Learn more
Two-storey side extensions
For homes in Barnsbury: typical guide from £103,500.
Learn more
Two-storey wraparound extensions
Barnsbury guide price from £144,500, Standard spec.
Learn more
Part single, part two-storey extensions
Barnsbury guide price from £86,500, Standard spec.
Learn more
Extensions over a garage
Barnsbury guide price from £38,000, Standard spec.
Learn more
First-floor extensions
From £30,000 in Barnsbury. Free visit to firm it up.
Learn more
Two-storey extensions for semi-detached houses
Barnsbury guide price from £67,000, Standard spec.
Learn more
Two-storey extensions for detached houses
For homes in Barnsbury: typical guide from £103,500.
Learn more
Kitchen extensions with bedrooms above
Barnsbury guide price from £67,000 (before kitchen units), Standard spec.
Learn more
Extra bedroom and en-suite extensions
Design, approvals and build for Barnsbury homes. Guide from £67,000 (plus en-suite).
Learn moreWhich type suits your house?
The boundaries usually decide it. Two-storey work close to a neighbour needs careful design for light and privacy, so at the visit in Barnsbury we measure distances to every boundary before suggesting a type.
Also available in Greater London
- Two-storey front extensions
- Two-storey extensions for end-of-terrace houses
- Two-storey annexe extensions
- Garage conversions with a room above
- Two-storey extension plans and drawings
- Planning permission for two-storey extensions
- Structural engineering for two-storey extensions
- Building regulations for two-storey extensions
- Party wall notices for extensions
- Design and build two-storey extensions
Rules for Barnsbury
Barnsbury is in England. Two-storey rear: up to 3 m deep and 7 m from the rear boundary under permitted development. Side, wraparound and front: planning permission. Householder planning application: £548 (or £575 for applications made from 8 December 2026). Lawful development certificate: £274 (about £288 for applications from 8 December 2026). Councils should decide householder applications within 8 weeks of validation.
The full England rules explained
Questions about extensions in Barnsbury
Do you cover Barnsbury?
Yes. We cover Barnsbury (N1C) and the surrounding area, including Islington and King's Cross. The first site visit is free.
What does a two-storey extension cost in Barnsbury?
Using our London guide, a two-storey rear extension with a 4 m × 3.5 m footprint on two floors (28 m² of new floor space) is about £67,000–£90,500 including VAT. An extension over a garage is about £38,000–£55,000.
Which other places near Barnsbury do you cover?
Everywhere around it, including Islington (0.7 miles), King's Cross (0.7 miles) and Holloway (0.9 miles), and the rest of Greater London.