What you could build at N7 8PL: the planning rules at this address, what neighbours have built and how big, planning decisions nearby, rough costs and the value an extension adds, and how to get started. In Highbury Fields, Islington.
122extensions seen within 600 m in the last 10 years
15loft conversions within 600 m in the last 10 years
80.8extensions per 1,000 homes in the neighbourhood (10 years)
● work seen on energy certificates · ● application approved · ● refused · ● pending or other · ● this postcode
The rules at this address
Mostly flats at this postcode. Flats have no permitted development rights, so almost any extension or loft conversion needs planning permission, and the freeholder's consent under the lease.
In the St Mary Magdalene conservation area: permitted development is narrower (for example no side extensions or roof cladding), and demolition and works to trees need consent.
No Article 4 direction recorded for this postcode.
Listed buildings need listed building consent for most changes, inside and out: check the National Heritage List.
To be certain work is permitted development, apply for a lawful development certificate (about £129 for householders in England). Building regulations apply either way.
Across England and Wales, homes extended by a typical 30 m² and then resold rose about 11.1% more than similar homes nearby over the same years (124,884 resales). How extensions pay off by size, type and region.
Single-storey rear or side extension: about £2,000–£3,000 per m² (London £2,500–£4,000), plus fees and VAT
Loft conversion: about £45,000–£75,000 for a dormer; more for a mansard or hip-to-gable
Two-storey extension: about £1,800–£2,800 per m² of new floor
Garage conversion: about £15,000–£30,000
Basement: about £3,500–£5,000 per m², London mostly
Build costs are rough 2026 ranges from industry guides, not quotes. Get three quotes for your plans.
Move or improve?
The money you don't get back either way, for the same extra space in Highbury Fields.
Move to a home 20 m² bigger (about £1,299,000)
Stamp duty on the new home
£73,650
Estate agent on yours 1.2% + VAT
£15,408
Solicitors, buying and selling
£3,000
Survey
£600
Removals
£1,500
Money gone
£94,158
Extend by 20 m²
Building, plus 15% for design, planning and contingency
£57,500
Less what it adds to your home's value 60% of the local price
−£137,400
Money gone
−£79,900
On these figures, extending loses about £174,058 less. Moving also changes the area, the schools and the commute; extending means months of building work and depends on planning.
Building costs vary a lot (a single-storey rear extension is often £2,000–£3,000 per m², more in London). How much space adds depends on the home and street: what extensions added to resale prices. A guide, not advice; nothing you type leaves this page.
Getting started
Look at what neighbours did. Open applications above to see drawings that were approved on similar houses, and who designed them.
Check the route: permitted development (with a lawful development certificate), prior approval for larger rear extensions, or full householder planning permission.
Get a measured survey and a designer: an architect, an architectural technologist or a designer who handles planning drawings.
Apply (householder permission is about £258 in England; councils aim to decide within 8 weeks).
Building regulations through the council's building control or an approved inspector, and party wall notices to neighbours if you build on or near the boundary.
Choose a builder: written quotes, a contract, staged payments, and check their insurance and references.
From energy certificates: an extension where a later certificate shows more floor space, a loft conversion where roof rooms appear. Certificates come with sales, lettings and some building work, so the year is when it was first seen.
Not every extension shows here. We only see building work when a new energy certificate is lodged, which happens when a home is sold, let or newly built. A loft or extension added since then won't appear, even with planning permission and building control sign-off, because those records aren't published as open data outside London. Missing work doesn't mean missing paperwork.
Windows, doors or cladding
Approved
–
P2026/0887/FUL
92, Lofting Road, N1 1jb
Loft or dormer
Approved
–
P2026/0855/FUL
12, Ringcroft Street, N7 8nd
Rear extension
Approved
–
P2026/0550/FUL
4, Crescent Street, N1 1bt
Rear extension
Approved
Apr 2026
P2026/0276/FUL
92, Offord Road, N1 1pf
Windows, doors or cladding
Approved
May 2026
P2026/0175/FUL
35, Crane Grove, N7 8ld
Two-storey extension
Approved
May 2026
P2025/3373/FUL
14, Melgund Road, N5 1pt
Loft or dormer
Other
Dec 2025
P2025/3044/COL
25, Bewdley Street, N1 1hb
Loft or dormer
Approved
Feb 2026
P2025/2498/FUL
35, Crane Grove, N7 8ld
Loft or dormer
Approved
Nov 2025
P2025/2502/FUL
1, Burness Close, N7 8sp
Side extension
Approved
Oct 2025
P2025/2325/FUL
31, Ronalds Road, N5 1xf
Loft or dormer
Approved
Sept 2025
P2025/2142/FUL
2, Bewdley Street, N1 1hb
Basement
Approved
Oct 2025
P2025/2119/FUL
39, Melgund Road, N5 1pt
Rear extension
Approved
Sept 2025
P2025/1925/FUL
32, College Cross, N1 1pr
Rear extension
Approved
Sept 2025
P2025/1971/FUL
14, Melgund Road, N5 1pt
Rear extension
Withdrawn
Sept 2025
P2025/1418/COL
9, Atlas Mews, N7 8xt
Loft or dormer
Other
May 2025
P2025/0882/COL
4, Horsell Road, N5 1xr
Loft or dormer
Other
Dec 2024
P2024/2991/COL
4, Horsell Road, N5 1xr
Rear extension
Refused
Dec 2024
P2024/2992/COL
Melgund Road, N5 1pt
Loft or dormer
Approved
Apr 2024
P2024/0210/FUL
24, Huntingdon Street, N1 1bs
Loft or dormer
Approved
Jan 2024
P2023/3135/FUL
Flat A, Westbourne Road, N7 8an
Other householder work
Refused
Jan 2024
P2023/3334/PRA
103, Westbourne Road, N7 8aa
Side extension
Other
Aug 2023
P2023/1930/COLP
20, Roman Way, N7 8xe
Loft or dormer
Withdrawn
Jul 2023
P2023/1802/COLP
41, Cornelia Street, N7 8ba
Outbuilding or garden room
Approved
Jul 2023
P2023/1253/FUL
103, Westbourne Road, N7 8aa
Rear extension
Other
May 2023
P2023/0866/COLP
103, Westbourne Road, N7 8aa
Loft or dormer
Other
May 2023
P2023/0838/COLP
26, Melgund Road, N5 1pt
Loft or dormer
Other
Apr 2023
P2023/0433/COLP
Householder applications validated since 2023 within 600 m. The council's page has the drawings, the decision notice and who the agent or architect was. Hover a row for the description. Source: GLA Planning London Datahub.
–
–
88%
8 weeks
Basement
–
80% (10)
83%
9 weeks
Porch or front extension
–
–
81%
8 weeks
Share of decided applications approved since 2023 (number decided in brackets). Withdrawn applications aren't counted; many are withdrawn when refusal looks likely.