What you could build at CR0 0DE: 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 New Addington South, Croydon.
35extensions seen within 600 m in the last 10 years
0loft conversions within 600 m in the last 10 years
69.3extensions 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 New Addington South.
Move to a home 20 m² bigger (about £482,000)
Stamp duty on the new home
£14,100
Estate agent on yours 1.2% + VAT
£5,616
Solicitors, buying and selling
£3,000
Survey
£600
Removals
£1,500
Money gone
£24,816
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
−£55,200
Money gone
£2,300
On these figures, extending loses about £22,516 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.
95, Godric Crescent, Cr0 0hx
Two-storey extension
Refused
Apr 2026
26/00381/HSE
40, Salcot Crescent, Cr0 0jh
Rear extension
Approved
Apr 2026
26/00470/GPDO
84, Montacute Road, Cr0 0je
Garage conversion or garage
Approved
Apr 2026
26/00491/HSE
232, Homestead Way, Cr0 0du
Loft or dormer
Approved
Apr 2026
26/00072/HSE
50, Gascoigne Road, Cr0 0nb
Two-storey extension
Approved
Feb 2026
25/04018/HSE
22, North Downs Road, Cr0 0lb
Side extension
Approved
Dec 2025
25/03610/HSE
33, North Downs Road, Cr0 0le
Loft or dormer
Approved
Nov 2025
25/02808/HSE
59, Windham Avenue, Cr0 0hz
Two-storey extension
Approved
Sept 2025
25/02441/HSE
52, Grenville Road, Cr0 0ny
Garage conversion or garage
Approved
Sept 2025
25/02363/HSE
52, Overbury Crescent, Cr0 0ln
Porch or front extension
Approved
Aug 2025
25/02149/HSE
67, Shaxton Crescent, Cr0 0nw
Rear extension
Approved
Jun 2025
25/01431/HSE
88, Parkway, Cr0 0la
Rear extension
Approved
May 2025
25/00892/HSE
109, Parkway, Cr0 0ja
Rear extension
Approved
Jun 2025
25/00933/HSE
31, Shaxton Crescent, Cr0 0nw
Rear extension
Refused
May 2025
25/00844/HSE
88, Parkway, Cr0 0la
Two-storey extension
Refused
Apr 2025
25/00469/HSE
61, Grenville Road, Cr0 0nz
Rear extension
Approved
Jan 2025
24/04207/GPDO
109, Parkway, Cr0 0ja
Rear extension
Approved
Jan 2025
24/04087/GPDO
275, Homestead Way, Cr0 0dz
Two-storey extension
Approved
Feb 2025
24/03752/HSE
14, Shaxton Crescent, Cr0 0nu
Side return or wrap-around
Approved
Dec 2024
24/03657/HSE
105, Parkway, Cr0 0ja
Porch or front extension
Approved
Dec 2024
24/03380/HSE
55, North Downs Road, Cr0 0le
Two-storey extension
Approved
Dec 2024
24/03193/HSE
136, Queen Elizabeth'S Drive, Cr0 0hf
Side extension
Approved
Feb 2025
24/02431/HSE
16, King Henry'S Drive, Cr0 0pa
Two-storey extension
Approved
Dec 2024
24/02199/HSE
37, Bothwell Road, Cr0 0nr
Two-storey extension
Approved
Aug 2024
24/02082/HSE
86, Montacute Road, Cr0 0je
Side extension
Approved
Jul 2024
24/01263/HSE
32, Overbury Crescent, Cr0 0ll
Two-storey extension
Approved
Sept 2024
24/01249/HSE
104, North Downs Road, Cr0 0ld
Rear extension
Approved
Jul 2024
24/01156/HSE
53, Windham Avenue, Cr0 0hz
Rear extension
Approved
May 2024
24/00814/GPDO
37, Salcot Crescent, Cr0 0jn
Two-storey extension
Approved
Mar 2024
24/00414/HSE
36, Bothwell Road, Cr0 0nr
Rear extension
Approved
Mar 2024
24/00034/HSE
42, Montacute Road, Cr0 0je
Outbuilding or garden room
Approved
Feb 2024
23/04678/HSE
32, Overbury Crescent, Cr0 0ll
Two-storey extension
Refused
Jan 2024
23/04227/HSE
126, Queen Elizabeth'S Drive, Cr0 0hf
Two-storey extension
Approved
Nov 2023
23/03240/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.