What you could build at CR0 4EW: 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 Waddon South, Croydon.
32extensions seen within 600 m in the last 10 years
2loft conversions within 600 m in the last 10 years
63.3extensions 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
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 Waddon South.
Move to a home 20 m² bigger (about £490,000)
Stamp duty on the new home
£14,500
Estate agent on yours 1.2% + VAT
£5,688
Solicitors, buying and selling
£3,000
Survey
£600
Removals
£1,500
Money gone
£25,288
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
−£57,000
Money gone
£500
On these figures, extending loses about £24,788 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.
Approved
Feb 2026
25/03771/HSE
107, Crowley Crescent, Cr0 4ef
Two-storey extension
Refused
Dec 2025
25/03450/HSE
99, Crowley Crescent, Cr0 4ef
Rear extension
Approved
Oct 2025
25/02831/GPDO
245, Violet Lane, Cr0 4hn
Side return or wrap-around
Refused
Apr 2026
25/02686/HSE
7, Hillier Gardens, Cr0 4eh
Rear extension
Approved
Sept 2025
25/02289/HSE
49, Coldharbour Road, Cr0 4dy
Two-storey extension
Approved
Jul 2025
25/01878/HSE
245, Violet Lane, Cr0 4hn
Rear extension
Approved
Jul 2025
25/01782/GPDO
3, Crowley Crescent, Cr0 4ee
Rear extension
Approved
Jun 2025
25/01558/HSE
41, Thorneloe Gardens, Cr0 4eq
Rear extension
Approved
Jun 2025
25/01486/GPDO
147, Stafford Road, Cr0 4nn
Rear extension
Approved
Jul 2025
25/01093/HSE
36, Waddon Way, Cr0 4hu
Rear extension
Approved
Apr 2025
25/00998/GPDO
16, Crowley Crescent, Cr0 4eb
Rear extension
Approved
Apr 2025
25/00712/GPDO
451, Waddon Leisure Centre, Purley Way, Cr0 4rg
Other householder work
Refused
Apr 2025
25/00215/GPDO
4, Waterworks Cottages, Waddon Way, Cr0 4hy
Two-storey extension
Approved
Apr 2025
25/00153/HSE
1, William'S Terrace, Cr0 4hz
Rear extension
Approved
Mar 2025
25/00065/HSE
1, William'S Terrace, Cr0 4hz
Garage conversion or garage
Refused
Mar 2025
25/00066/HSE
18, Cosedge Crescent, Cr0 4dn
Two-storey extension
Approved
Apr 2025
25/00008/HSE
92, Stafford Road, Cr0 4nf
Rear extension
Approved
Mar 2025
23/04635/HSE
64, Barrow Road, Cr0 4ey
Porch or front extension
Approved
Mar 2025
24/02501/HSE
575, Purley Way, Cr0 4rj
Rear extension
Refused
Jan 2025
24/04023/GPDO
34, Denning Avenue, Cr0 4de
Loft or dormer
Approved
Dec 2024
24/03743/HSE
11, Fernleigh Close, Cr0 4ry
Side extension
Approved
Nov 2024
24/03103/HSE
37, Foss Avenue, Cr0 4ew
Rear extension
Approved
Nov 2024
24/03083/GPDO
14, Barrow Road, Cr0 4ey
Loft or dormer
Approved
May 2025
24/02725/HSE
16, Barrow Road, Cr0 4ey
Loft or dormer
Approved
May 2025
24/02726/HSE
20, Merebank Lane, Cr0 4np
Rear extension
Not needed / lawful
Sept 2024
DM2024/01039
575, Purley Way, Cr0 4rj
Rear extension
Refused
Aug 2024
24/02521/GPDO
68, Crowley Crescent, Cr0 4eb
Rear extension
Approved
Sept 2024
24/02265/HSE
54, Denning Avenue, Cr0 4df
Outbuilding or garden room
Approved
Jul 2024
24/01740/HSE
72, Crowley Crescent, Cr0 4ed
Loft or dormer
Approved
Aug 2024
24/01439/HSE
14, Barrow Road, Cr0 4ey
Rear extension
Approved
Jun 2024
24/01629/GPDO
16, Barrow Road, Cr0 4ey
Rear extension
Approved
Jun 2024
24/01630/GPDO
1, William'S Terrace, Cr0 4hz
Porch or front extension
Refused
Jun 2024
24/00759/HSE
1, Coldharbour Road, Cr0 4dy
Rear extension
Approved
May 2024
24/01318/GPDO
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.