What you could build at SW9 8BS: 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 Brixton Central, Lambeth.
212extensions seen within 600 m in the last 10 years
33loft conversions within 600 m in the last 10 years
81.9extensions 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 Brixton Central.
Move to a home 20 m² bigger (about £639,000)
Stamp duty on the new home
£21,950
Estate agent on yours 1.2% + VAT
£7,128
Solicitors, buying and selling
£3,000
Survey
£600
Removals
£1,500
Money gone
£34,178
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
−£86,400
Money gone
−£28,900
On these figures, extending loses about £63,078 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.
5, 5 Ducie Street London Lambeth Sw4 7rp, Ducie Street, Sw4 7rp
Loft or dormer
Approved
Jun 2026
25/03780/FUL
57, Tasman Road, Sw9 9lz
Loft or dormer
Approved
Apr 2026
26/00157/LDCE
188, Stockwell Road, Sw9 9tf
Loft or dormer
Refused
Mar 2026
26/00112/LDCP
6, Santley Street, Sw4 7qb
Loft or dormer
Refused
Jan 2026
25/03267/LDCP
23, Mervan Road, Sw2 1dp
Loft or dormer
Approved
Nov 2025
25/03063/LDCP
25, 25 Stockwell Green London Lambeth Sw9 9hz, Stockwell Green, Sw9 9hz
83 Hargwyne Street London Lambeth Sw9 9rh, Hargwyne Street, Sw9 9rh
Loft or dormer
Approved
Jun 2025
25/00462/LDCP
35, Tunstall Road, Sw9 8bz
Loft or dormer
Refused
Apr 2025
25/00343/LDCP
Hereford House, Rushcroft Road, Sw2 1lq
Loft or dormer
Approved
Apr 2025
25/00447/LDCE
25, Talma Road, Sw2 1au
Loft or dormer
Approved
Mar 2025
25/00232/LDCP
17, Saltoun Road, Sw2 1en
Loft or dormer
Approved
Feb 2025
24/03982/LDCP
25, Talma Road, Sw2 1au
Loft or dormer
Approved
Dec 2024
24/03433/LDCP
23, Talma Road, Sw2 1au
Loft or dormer
Approved
Dec 2024
24/03415/LDCP
146a, 148, Stockwell Road, Sw9 9tq
Other householder work
Refused
Nov 2024
24/02967/P3MA
409, 411, Brixton Road, Sw9 7dg
Other householder work
Refused
Nov 2024
24/02845/P3MA
60 Kellett Road London Lambeth Sw2 1ed
Loft or dormer
Approved
Sept 2024
24/02271/LDCP
409, 411, Brixton Road, Sw9 7dg
Other householder work
Refused
Sept 2024
24/02108/P3G
174, Ferndale Road, Sw9 8al
Loft or dormer
Refused
Jul 2024
24/01037/LDCP
16 Bankton Road London Lambeth Sw2 1bs
Side extension
Refused
May 2024
24/01078/PDE
16, Bankton Road, Sw2 1bs
Loft or dormer
Approved
Mar 2024
24/00379/LDCP
16, Bankton Road, Sw2 1bs
Side extension
Refused
Mar 2024
24/00380/LDCP
1, Mordaunt Street, Sw9 9rd
Side return or wrap-around
Refused
Mar 2024
24/00337/LDCP
13 Baytree Road London Lambeth Sw2 5rr
Loft or dormer
Approved
Dec 2023
23/03322/LDCP
60, Dalyell Road, Sw9 9up
Side return or wrap-around
Approved
Dec 2023
23/03274/LDCE
5, 5 Glendall Street London Lambeth Sw9 8aj, Glendall Street, Sw9 8aj
Loft or dormer
Approved
Dec 2023
23/03144/FUL
4, 4 Raeburn Street London Lambeth Sw2 5qu, Raeburn Street, Sw2 5qu
Side return or wrap-around
Approved
Oct 2023
23/02949/PDE
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% (16)
88%
8 weeks
Basement
–
50% (8)
83%
15 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.