What you could build at CR7 7HS: 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 West Thornton North, Croydon.
126extensions seen within 600 m in the last 10 years
9loft conversions within 600 m in the last 10 years
84extensions 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 West Thornton North.
Move to a home 20 m² bigger (about £556,000)
Stamp duty on the new home
£17,800
Estate agent on yours 1.2% + VAT
£6,696
Solicitors, buying and selling
£3,000
Survey
£600
Removals
£1,500
Money gone
£29,596
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
−£54,600
Money gone
£2,900
On these figures, extending loses about £26,696 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.
68, Keston Road, Cr7 6bs
Rear extension
Refused
Jun 2026
26/01400/GPDO
322, Brigstock Road, Cr7 7jf
Rear extension
Approved
May 2026
26/01183/GPDO
61, Penshurst Road, Cr7 7ef
Rear extension
Approved
Jun 2026
26/01150/GPDO
89, Broughton Road, Cr7 6aj
Rear extension
Approved
May 2026
26/01010/GPDO
8, Keston Road, Cr7 6bs
Rear extension
Approved
Apr 2026
26/00786/GPDO
13, Frant Road, Cr7 7jy
Rear extension
Approved
Jun 2026
26/00292/HSE
58, Raymead Avenue, Cr7 7sa
Rear extension
Refused
Apr 2026
26/00761/GPDO
29, Lakehall Road, Cr7 7eg
Rear extension
Refused
Apr 2026
26/00301/HSE
43, Broughton Road, Cr7 6ag
Rear extension
Approved
Feb 2026
25/04136/GPDO
8, Keston Road, Cr7 6bs
Rear extension
Approved
Feb 2026
25/04034/GPDO
2, Dunheved Close, Cr7 6aq
Rear extension
Approved
Feb 2026
25/03907/HSE
52, Limpsfield Avenue, Cr7 6be
Rear extension
Approved
Jan 2026
25/03957/GPDO
65, Woodcroft Road, Cr7 7hb
Loft or dormer
Approved
Dec 2025
25/03324/HSE
36, Harcourt Road, Cr7 6bu
Loft or dormer
Approved
Nov 2025
25/02741/GPDO
52, Limpsfield Avenue, Cr7 6be
Rear extension
Refused
Oct 2025
25/03059/GPDO
28, Nutfield Road, Cr7 7dl
Rear extension
Approved
Oct 2025
25/02759/GPDO
10, Dunheved Road West, Cr7 6ap
Rear extension
Refused
Sept 2025
25/01595/GPDO
335, Bensham Lane, Cr7 7er
Rear extension
Approved
Sept 2025
25/02691/GPDO
17, Curzon Road, Cr7 6br
Rear extension
Approved
Sept 2025
25/02695/GPDO
1, Cheltenham Villas, Stanley Road, Cr0 3qa
Garage conversion or garage
Approved
Oct 2025
25/02239/HSE
37, Malvern Road, Cr7 7lu
Rear extension
Approved
Jul 2025
25/01966/GPDO
43, Dovercourt Avenue, Cr7 7lj
Rear extension
Refused
Jul 2025
25/01898/GPDO
41, Keston Road, Cr7 6bt
Rear extension
Approved
Jul 2025
25/01591/GPDO
68, Limpsfield Avenue, Cr7 6bf
Rear extension
Approved
Jun 2025
25/01221/HSE
14, Keston Road, Cr7 6bs
Loft or dormer
Approved
Jul 2025
25/01187/HSE
14, Southwell Road, Cr0 3qd
Rear extension
Approved
Jun 2025
25/00659/HSE
1, Whitehall Road, Cr7 6af
Rear extension
Approved
Jun 2025
25/01010/HSE
12, Fairlands Avenue, Cr7 6ha
Rear extension
Approved
Apr 2025
25/00970/GPDO
111, Lakehall Road, Cr7 7ej
Rear extension
Approved
May 2025
25/00542/HSE
33, Haslemere Road, Cr7 7bf
Side return or wrap-around
Refused
Jun 2025
25/00325/HSE
8, Cheltenham Villas, Stanley Road, Cr0 3qa
Rear extension
Approved
Apr 2025
25/00270/HSE
99, Frant Road, Cr7 7jx
Rear extension
Approved
Mar 2025
25/00009/GPDO
19, Weybridge Road, Cr7 7ln
Outbuilding or garden room
Approved
Jan 2025
24/03884/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.