What you could build at SW16 3LZ: 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 Norbury East, Croydon.
68extensions seen within 600 m in the last 10 years
5loft conversions within 600 m in the last 10 years
78.1extensions 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 Norbury East.
Move to a home 20 m² bigger (about £565,000)
Stamp duty on the new home
£18,250
Estate agent on yours 1.2% + VAT
£6,912
Solicitors, buying and selling
£3,000
Survey
£600
Removals
£1,500
Money gone
£30,262
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
−£51,000
Money gone
£6,500
On these figures, extending loses about £23,762 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.
26/01351/HSE
271, Green Lane, Sw16 3ly
Loft or dormer
Approved
Jul 2026
26/01291/HSE
13, Covington Gardens, Sw16 3se
Two-storey extension
Refused
Jul 2026
26/00888/HSE
39, Christian Fields, Sw16 3jy
Garage conversion or garage
Approved
Jun 2026
26/01018/HSE
137, Green Lane, Sw16 3na
Rear extension
Approved
Apr 2026
26/00895/GPDO
118, Green Lane, Sw16 3nb
Two-storey extension
Approved
May 2026
26/00455/HSE
195, Green Lane, Sw16 3lz
Rear extension
Approved
Mar 2026
26/00332/GPDO
24, Hillcote Avenue, Sw16 3bq
Two-storey extension
Approved
Apr 2026
25/03994/HSE
153, Green Lane, Sw16 3na
Two-storey extension
Approved
Mar 2026
25/04106/HSE
11, The Chase, Sw16 3ae
Rear extension
Approved
Mar 2026
25/04006/HSE
195, Green Lane, Sw16 3lz
Rear extension
Refused
Jan 2026
25/04008/GPDO
118, Green Lane, Sw16 3nb
Rear extension
Approved
Dec 2025
25/03729/GPDO
19, Groveland Avenue, Sw16 3bg
Outbuilding or garden room
Approved
Jan 2026
25/03398/HSE
89, Christian Fields, Sw16 3ju
Outbuilding or garden room
Approved
Dec 2025
25/03279/HSE
272, Green Lane, Sw16 3ba
Two-storey extension
Approved
Nov 2025
25/02923/HSE
249, Norbury Avenue, Sw16 3rn
Rear extension
Approved
Oct 2025
25/02401/HSE
140, Green Lane, Sw16 3ne
Rear extension
Approved
Oct 2025
25/02926/GPDO
225, Norbury Avenue, Cr7 8ab
Rear extension
Approved
Oct 2025
25/02919/GPDO
34, Bigginwood Road, Sw16 3rz
Loft or dormer
Approved
Nov 2025
25/02694/HSE
118, Green Lane, Sw16 3nb
Loft or dormer
Refused
Oct 2025
25/02737/HSE
74, Christian Fields, Sw16 3jx
Outbuilding or garden room
Approved
Oct 2025
25/02687/HSE
91, Green Lane, Cr7 8bj
Two-storey extension
Approved
Sept 2025
25/02404/HSE
13, Christian Fields, Sw16 3jy
Other householder work
Approved
Aug 2025
25/02472/GPDO
137, Covington Way, Sw16 3jt
Rear extension
Approved
Sept 2025
25/02095/HSE
17, Christian Fields, Sw16 3jy
Rear extension
Approved
Aug 2025
25/02278/GPDO
246, Norbury Avenue, Sw16 3rn
Loft or dormer
Approved
Sept 2025
25/02337/HSE
321, Norbury Avenue, Sw16 3rw
Basement
Under consideration
–
25/01636/HSE
41, Kensington Avenue, Cr7 8bt
Porch or front extension
Approved
Aug 2025
25/02142/HSE
13, Christian Fields, Sw16 3jy
Rear extension
Refused
Jul 2025
25/02125/GPDO
54, Buckingham Avenue, Cr7 8as
Rear extension
Approved
Nov 2025
25/01972/HSE
16, Virginia Road, Cr7 8eg
Loft or dormer
Approved
Jul 2025
25/01557/HSE
225, Norbury Avenue, Cr7 8ab
Rear extension
Approved
Jul 2025
25/01642/GPDO
40, Briar Avenue, Sw16 3aa
Loft or dormer
Approved
Jul 2025
25/01643/HSE
41, Croft Road, Sw16 3ng
Loft or dormer
Approved
Jun 2025
25/01396/HSE
36, Norbury Hill, Sw16 3lb
Two-storey extension
Approved
Jul 2025
25/00464/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.