What you could build at N18 2NS: 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 Upper Edmonton East & Meridian Water, Enfield.
45extensions seen within 600 m in the last 10 years
3loft conversions within 600 m in the last 10 years
108.2extensions 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
Houses usually have permitted development rights: some rear extensions (typically up to 3 m deep for a semi or terrace, 4 m detached), loft conversions within volume limits, and porches can go ahead without planning permission. Larger single-storey rear extensions (up to 6 m / 8 m) can use the “prior approval” neighbour scheme.
Not in a conservation area (from council registers).
Article 4 direction (Borough wide): some rights normally allowed have been removed here. Check what it covers with the council before relying on permitted development.
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 Upper Edmonton East & Meridian Water.
Move to a home 20 m² bigger (about £504,000)
Stamp duty on the new home
£15,200
Estate agent on yours 1.2% + VAT
£5,832
Solicitors, buying and selling
£3,000
Survey
£600
Removals
£1,500
Money gone
£26,132
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
−£59,400
Money gone
−£1,900
On these figures, extending loses about £28,032 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.
Approved
Jul 2026
26/01491/HOU
2a, Ellanby Crescent, N18 2hh
Loft or dormer
Refused
Jul 2026
26/01575/HOU
84, Montagu Crescent, N18 2ha
Windows, doors or cladding
Approved
May 2026
26/00803/HOU
22, Montagu Crescent, N18 2ha
Windows, doors or cladding
Approved
Jun 2026
26/00802/HOU
4, St Peters Avenue, N18 2px
Rear extension
Approved
May 2026
26/01087/HOU
4, Cameron Close, N18 2hl
Other householder work
Approved
May 2026
26/00708/HOU
5, Cavendish Road, N18 2lu
Rear extension
Not needed / lawful
Apr 2026
26/01034/PRH
53, Dysons Road, N18 2dg
Rear extension
Approved
Mar 2026
26/00482/PRH
39, Montagu Gardens, N18 2hb
Rear extension
Not needed / lawful
Mar 2026
26/00491/PRH
34, Berkshire Gardens, N18 2lf
Two-storey extension
Refused
Mar 2026
26/00156/HOU
8, Cameron Close, N18 2hl
Rear extension
Not needed / lawful
Nov 2025
25/03529/PRH
57, Kings Road, N18 2qs
Loft or dormer
Refused
Nov 2025
25/03123/HOU
34, Berkshire Gardens, N18 2lf
Rear extension
Not needed / lawful
Jul 2025
25/01974/PRH
9, Ellanby Crescent, N18 2hj
Rear extension
Not needed / lawful
Jun 2025
25/01688/PRH
59, Cavendish Road, N18 2lt
Rear extension
Not needed / lawful
Apr 2025
25/00686/PRH
8, Glasgow Road, N18 2eg
Two-storey extension
Approved
Mar 2025
24/02873/HOU
32, Brook Crescent, N9 0dj
Outbuilding or garden room
Approved
Mar 2025
24/03893/HOU
74, Fraser Road, N9 0bx
Two-storey extension
Approved
Feb 2025
24/03472/HOU
57, Cavendish Road, N18 2lt
Rear extension
Not needed / lawful
Oct 2024
24/03110/PRH
74, Fraser Road, N9 0bx
Two-storey extension
Refused
Oct 2024
24/02742/HOU
9, Ascot Road, N18 2pu
Rear extension
Approved
Sept 2024
24/02511/HOU
72, Fraser Road, N9 0bx
Rear extension
Not needed / lawful
Aug 2024
24/02230/PRH
68, Brookfield Road, N9 0dg
Rear extension
Not needed / lawful
Jul 2024
24/02015/PRH
51, Brookfield Road, N9 0dh
Two-storey extension
Approved
May 2024
24/00805/HOU
74, Fraser Road, N9 0bx
Rear extension
Not needed / lawful
Mar 2024
24/00196/PRH
57, Kings Road, N18 2qs
Outbuilding or garden room
Approved
Feb 2024
23/03904/HOU
51, Brookfield Road, N9 0dh
Two-storey extension
Withdrawn
Dec 2023
23/03491/HOU
66, Fraser Road, N9 0bx
Other householder work
Approved
Dec 2023
23/03384/HOU
29, Montagu Crescent, N18 2ha
Rear extension
Approved
Nov 2023
23/03008/HOU
2, Lansfield Avenue, N18 2pt
Rear extension
Refused
Oct 2023
23/02525/HOU
3, Brook Crescent, N9 0dj
Two-storey extension
Approved
Oct 2023
23/02817/HOU
66, Fraser Road, N9 0bx
Side extension
Refused
Oct 2023
23/02522/HOU
1, North Avenue, N18 2ps
Two-storey extension
Approved
Aug 2023
23/01955/HOU
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.
–
85% (116)
88%
7 weeks
Basement
–
53% (17)
83%
8 weeks
Porch or front extension
–
88% (74)
81%
7 weeks
Share of decided applications approved since 2023 (number decided in brackets). Withdrawn applications aren't counted; many are withdrawn when refusal looks likely.