What you could build at BR5 2PQ: 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 St Mary Cray North, Bromley.
39extensions seen within 600 m in the last 10 years
3loft conversions within 600 m in the last 10 years
79.1extensions 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 St Mary Cray North.
Move to a home 20 m² bigger (about £521,000)
Stamp duty on the new home
£16,050
Estate agent on yours 1.2% + VAT
£6,048
Solicitors, buying and selling
£3,000
Survey
£600
Removals
£1,500
Money gone
£27,198
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
−£60,600
Money gone
−£3,100
On these figures, extending loses about £30,298 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.
7, Batchwood Green, Br5 2ne
Loft or dormer
Approved
Feb 2025
24/03888/FULL6
7, Batchwood Green, Br5 2ne
Rear extension
Not needed / lawful
Nov 2024
24/03895/HHPA
32, Trentham Drive, Br5 2ep
Two-storey extension
Approved
Dec 2024
24/03886/FULL6
15, Priorsford Avenue, Br5 2en
Rear extension
Approved
Mar 2025
24/03689/FULL6
46, Ringshall Road, Br5 2lz
Rear extension
Approved
Nov 2024
24/03277/FULL6
18, Vernon Close, Br5 3as
Rear extension
Approved
Sept 2024
24/03012/FULL6
32, Trentham Drive, Br5 2ep
Two-storey extension
Refused
Sept 2024
24/02705/FULL6
11, Meath Close, Br5 2hf
Rear extension
Approved
Aug 2024
24/02661/FULL6
56, Cray Valley Road, Br5 2ez
Two-storey extension
Approved
Oct 2024
24/01950/FULL6
14, Sayes Court Road, Br5 2pq
Rear extension
Not needed / lawful
Jun 2024
24/01989/HHPA
5, Longbury Close, Br5 2lb
Other householder work
Refused
Jul 2024
24/01941/FULL6
10, Sunnyfield Road, Br7 6qp
Rear extension
Approved
Jul 2024
24/01843/FULL6
25, Longbury Drive, Br5 2ju
Rear extension
Not needed / lawful
Apr 2024
24/00995/HHPA
21, Curtismill Close, Br5 2jx
Two-storey extension
Approved
Apr 2024
24/00622/FULL6
19, Marion Crescent, Br5 2de
Loft or dormer
Approved
Mar 2024
24/00316/FULL6
138, Amherst Drive, Br5 2hj
Rear extension
Approved
Mar 2024
24/00055/FULL6
62, Marion Crescent, Br5 2hd
Side extension
Approved
Jan 2024
23/04519/FULL6
161, Ravensbury Road, Br5 2nl
Rear extension
Approved
Feb 2024
23/04460/FULL6
55, Hayfield Road, Br5 2dl
Side extension
Approved
Dec 2023
23/03974/FULL6
65, Clarendon Green, Br5 2nz
Other householder work
Approved
Dec 2023
23/03683/FULL6
16, May Avenue, Br5 2ed
Two-storey extension
Approved
Nov 2023
23/03597/FULL6
19, Trentham Drive, Br5 2ep
Rear extension
Not needed / lawful
Oct 2023
23/03505/HHPA
16, May Avenue, Br5 2ed
Two-storey extension
Refused
Sept 2023
23/02752/FULL6
51, Furzehill Square, Br5 3sn
Rear extension
Approved
Jan 2024
23/02677/FULL6
141, Leesons Hill, Br5 2ng
Loft or dormer
Approved
Aug 2023
23/02259/FULL6
10, Longbury Drive, Br5 2ju
Loft or dormer
Refused
Aug 2023
23/01987/FULL6
45, Millfields Close, Br5 2lq
Rear extension
Approved
Jun 2023
23/01671/FULL6
47, Furzehill Square, Br5 3sn
Rear extension
Approved
Jun 2023
23/01379/FULL6
130, Leesons Hill, Br5 2nh
Rear extension
Approved
Jun 2023
23/01353/FULL6
33, Ravensbury Road, Br5 2nr
Other householder work
Approved
May 2023
23/01123/FULL6
33, Ravensbury Road, Br5 2nr
Rear extension
Not needed / lawful
Apr 2023
23/01122/HHPA
76, Ravensbury Road, Br5 2nn
Rear extension
Not needed / lawful
Apr 2023
23/00897/HHPA
47, Furzehill Square, Br5 3sn
Rear extension
Not needed / lawful
Mar 2023
23/00681/HHPA
39, Lynton Avenue, Br5 2eh
Rear extension
Refused
Mar 2023
23/00273/HHPA
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.
–
85% (123)
88%
8 weeks
Basement
–
77% (26)
83%
9 weeks
Porch or front extension
–
92% (94)
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.