What you could build at SE25 5AB: 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 South Norwood Hill, Croydon.
105extensions seen within 600 m in the last 10 years
14loft conversions within 600 m in the last 10 years
58.1extensions 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).
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 South Norwood Hill.
Move to a home 20 m² bigger (about £488,000)
Stamp duty on the new home
£14,400
Estate agent on yours 1.2% + VAT
£5,400
Solicitors, buying and selling
£3,000
Survey
£600
Removals
£1,500
Money gone
£24,900
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
−£67,800
Money gone
−£10,300
On these figures, extending loses about £35,200 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.
654, Davidson Road, Cr0 6dj
Rear extension
Approved
Jan 2026
25/03871/GPDO
654, Davidson Road, Cr0 6dj
Rear extension
Refused
Nov 2025
25/03345/GPDO
33, Stanger Road, Se25 5jz
Rear extension
Approved
Oct 2025
25/02746/HSE
50, South Norwood Hill, Se25 6af
Loft or dormer
Approved
Nov 2025
25/02275/HSE
112a, Crowther Road, Se25 5qs
Side return or wrap-around
Approved
Aug 2025
25/01177/HSE
654, Davidson Road, Cr0 6dj
Rear extension
Approved
May 2025
25/00740/HSE
116, Crowther Road, Se25 5qs
Rear extension
Approved
Apr 2025
25/00965/GPDO
238, Holmesdale Road, Se25 6pt
Rear extension
Approved
Apr 2025
25/00615/GPDO
17, Birchanger Road, Se25 5ba
Rear extension
Approved
Sept 2025
25/00147/HSE
122, Tennison Road, Se25 5ne
Other householder work
Approved
Feb 2025
24/04050/HSE
2, Elm Park Road, Se25 6ua
Rear extension
Approved
Feb 2025
25/00039/HSE
4, Sunnycroft Road, Se25 4tb
Rear extension
Approved
Feb 2025
24/04262/HSE
33, Stanger Road, Se25 5jz
Side return or wrap-around
Refused
Jan 2025
24/03863/HSE
9, Albert Road, Se25 4jd
Two-storey extension
Approved
Jan 2025
24/03688/HSE
116, Crowther Road, Se25 5qs
Loft or dormer
Under consideration
–
24/02121/HSE
168l, Selhurst Road, Se25 6ly
Other householder work
Approved
Dec 2024
24/03448/HSE
654, Davidson Road, Cr0 6dj
Rear extension
Refused
Dec 2024
24/03559/HSE
14, Dinsdale Gardens, Se25 6lt
Rear extension
Approved
Oct 2024
24/02920/HSE
44, Birchanger Road, Se25 5bb
Loft or dormer
Under consideration
–
24/03036/HSE
9, Albert Road, Se25 4jd
Loft or dormer
Approved
Jan 2025
24/02570/HSE
11, Wynton Gardens, Se25 5rs
Two-storey extension
Approved
Oct 2024
24/01934/HSE
54, Bungalow Road, Se25 6jz
Rear extension
Approved
Jul 2024
24/02246/GPDO
654, Davidson Road, Cr0 6dj
Rear extension
Refused
Jul 2024
24/02065/GPDO
595, Davidson Road, Cr0 6du
Outbuilding or garden room
Approved
Jul 2024
24/01837/HSE
10, Sunnycroft Road, Se25 4tb
Loft or dormer
Approved
Jul 2024
24/01836/HSE
5, Broster Gardens, Se25 6tx
Rear extension
Approved
Jul 2024
24/01501/HSE
107, Crowther Road, Se25 5qs
Loft or dormer
Refused
May 2024
24/01348/HSE
28, Balfour Road, Se25 5jy
Outbuilding or garden room
Approved
May 2024
24/01123/HSE
23, Huntly Road, Se25 6qy
Side return or wrap-around
Approved
Apr 2024
24/00948/HSE
11, Wynton Gardens, Se25 5rs
Rear extension
Approved
Apr 2024
24/00559/GPDO
107, Crowther Road, Se25 5qs
Loft or dormer
Refused
Mar 2024
24/00551/HSE
654, Davidson Road, Cr0 6dj
Rear extension
Refused
Mar 2024
24/00167/HSE
54, Bungalow Road, Se25 6jz
Loft or dormer
Refused
Feb 2024
24/00027/HSE
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% (122)
88%
8 weeks
Basement
–
74% (57)
83%
8 weeks
Porch or front extension
–
88% (65)
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.