What you could build at SE15 3BE: 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 Nunhead South & Newlands, Southwark.
128extensions seen within 600 m in the last 10 years
7loft conversions within 600 m in the last 10 years
130.4extensions 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.
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 Nunhead South & Newlands.
Move to a home 20 m² bigger (about £929,000)
Stamp duty on the new home
£36,650
Estate agent on yours 1.2% + VAT
£11,160
Solicitors, buying and selling
£3,000
Survey
£600
Removals
£1,500
Money gone
£52,910
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
−£92,400
Money gone
−£34,900
On these figures, extending loses about £87,810 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.
Jun 2026
26/AP/1270
81, Athenlay Road, Se15 3en
Rear extension
Approved
Jun 2026
26/AP/1155
257e, Peckham Rye, Se15 3ab
Rear extension
Withdrawn
Jun 2026
26/AP/0991
185, Peckham Rye, Se15 3hz
Rear extension
Approved
May 2026
26/AP/0786
27, Stuart Road, Se15 3be
Rear extension
Approved
Apr 2026
26/AP/0681
129, Athenlay Road, Se15 3ej
Loft or dormer
Approved
Apr 2026
26/AP/0595
27, Surrey Road, Se15 3as
Loft or dormer
Approved
Apr 2026
26/AP/0570
20, Harlescott Road, Se15 3bz
Side return or wrap-around
Approved
Apr 2026
26/AP/0394
38, Mundania Road, Se22 0nw
Other householder work
Approved
Mar 2026
26/AP/0295
20, Harlescott Road, Se15 3bz
Loft or dormer
Approved
Mar 2026
26/AP/0307
25, Hichisson Road, Se15 3an
Loft or dormer
Approved
Mar 2026
26/AP/0119
14, Merttins Road, Se15 3eb
Loft or dormer
Approved
Feb 2026
26/AP/0102
6, Lanbury Road, Se15 3db
Loft or dormer
Approved
Apr 2026
26/AP/0006
2, Homeleigh Road, Se15 3ee
Side extension
Approved
Feb 2026
25/AP/3629
220, Ivydale Road, Se15 3bu
Loft or dormer
Approved
Feb 2026
25/AP/3673
37, Athenlay Road, Se15 3ea
Loft or dormer
Approved
Jan 2026
25/AP/3445
37, Athenlay Road, Se15 3ea
Loft or dormer
Approved
Dec 2025
25/AP/3451
22, Harlescott Road, Se15 3bz
Loft or dormer
Approved
Feb 2026
25/AP/3284
22, Harlescott Road, Se15 3bz
Loft or dormer
Approved
Jan 2026
25/AP/3283
36, Hichisson Road, Se15 3al
Side return or wrap-around
Approved
Dec 2025
25/AP/3082
317, Ivydale Road, Se15 3dz
Loft or dormer
Approved
Nov 2025
25/AP/3014
135, Ivydale Road, Se15 3dx
Loft or dormer
Approved
Dec 2025
25/AP/2939
211, Ivydale Road, Se15 3dy
Loft or dormer
Approved
Nov 2025
25/AP/2758
43, Surrey Road, Se15 3as
Loft or dormer
Approved
Dec 2025
25/AP/2881
68, Homestall Road, Se22 0sb
Loft or dormer
Approved
Oct 2025
25/AP/2577
53, Hichisson Road, Se15 3an
Loft or dormer
Approved
Oct 2025
25/AP/2534
30, Reynolds Road, Se15 3ah
Loft or dormer
Approved
Nov 2025
25/AP/2460
11, Scutari Road, Se22 0nn
Rear extension
Approved
Oct 2025
25/AP/2087
24, Colyton Road, Se22 0np
Rear extension
Approved
Sept 2025
25/AP/2250
40, Cheltenham Road, Se15 3aq
Side return or wrap-around
Approved
Sept 2025
25/AP/2111
29, Stuart Road, Se15 3be
Loft or dormer
Approved
Aug 2025
25/AP/1872
50, Hichisson Road, Se15 3al
Side return or wrap-around
Approved
Aug 2025
25/AP/1648
9, Rosenthorpe Road, Se15 3eg
Rear extension
Approved
Jul 2025
25/AP/1386
50, Hichisson Road, Se15 3al
Loft or dormer
Approved
Jul 2025
25/AP/1630
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.
–
100% (47)
88%
7 weeks
Basement
–
96% (47)
83%
8 weeks
Porch or front extension
–
100% (19)
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.