What you could build at W12 7RG: 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 Old Oak & Wormwood, Hammersmith and Fulham.
34extensions seen within 600 m in the last 10 years
3loft conversions within 600 m in the last 10 years
64.1extensions 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
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.
In the Wood Lane conservation area: permitted development is narrower (for example no side extensions or roof cladding), and demolition and works to trees need consent.
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 Old Oak & Wormwood.
Move to a home 20 m² bigger (about £651,000)
Stamp duty on the new home
£22,550
Estate agent on yours 1.2% + VAT
£7,488
Solicitors, buying and selling
£3,000
Survey
£600
Removals
£1,500
Money gone
£35,138
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
−£78,600
Money gone
−£21,100
On these figures, extending loses about £56,238 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.
Side return or wrap-around
Approved
Apr 2025
PP/25/00883
94, Frithville Gardens, W12 7jw
Rear extension
Approved
Mar 2025
2025/00208/PD42
Artist'S Studio, 41 Mary Place, London, W11 4pl
Other householder work
Withdrawn
Jan 2025
CL/24/07570
Residence R1, 41 Mary Place, London, W11 4pl
Other householder work
Withdrawn
Jan 2025
CL/24/07572
Land To The Rear Of 12 Olaf Street And Opposite Rear Of 3 Olaf Street London
Other householder work
Withdrawn
Dec 2024
2024/02628/CLP
341a Latimer Road, London, W10 6ra
Other householder work
Approved
Jan 2025
PP/24/06583
97-101 Wilsham Street, London, W11 4au
Loft or dormer
Approved
Oct 2024
PP/24/06089
97-101 And 103 Wilsham Street, London, W11 4au
Other householder work
Approved
Aug 2024
CL/24/05177
97-101 Wilsham Street, London, W11 4au
Loft or dormer
Withdrawn
Aug 2024
PP/24/04400
97-101 Wilsham Street, London, W11 4au
Loft or dormer
Withdrawn
Jun 2024
CL/24/03780
21 Silchester Road, London, W10 6sf
Other householder work
Approved
Dec 2024
PP/24/03262
143 Oxford Gardens, London, W10 6ne
Side return or wrap-around
Approved
Jun 2024
PP/24/02671
26 Treadgold Street, London, W11 4bp
Loft or dormer
Approved
Jun 2024
PP/24/02025
97-101 And 103 Wilsham Street, London, W11 4au
Other householder work
Refused
Mar 2024
CL/24/00533
341, 341a Latimer Road, London, W10 6ra
Other householder work
Approved
May 2024
PP/23/08055
25 Balliol Road, London, W10 6lx
Other householder work
Approved
Feb 2024
PP/23/06969
1 Highlever Road, London, W10 6pp
Loft or dormer
Approved
Oct 2023
PP/23/05337
20 St Ann'S Road, London, W11 4sr
Other householder work
Approved
Oct 2023
PP/23/05297
Westfield London Shopping Centre, Ariel Way
Other householder work
Approved
Sept 2023
2023/01724/PDJ56
25 Balliol Road, London, W10 6lx
Other householder work
Withdrawn
May 2023
PP/23/02726
7 Darnley Terrace, London, W11 4rl
Loft or dormer
Approved
Jun 2023
PP/23/02645
20 St Ann'S Road, London, W11 4sr
Other householder work
Withdrawn
Jun 2023
PP/23/02390
Opposite Goodrich Court, On Darfield Way, London, W10 6rh
Other householder work
Approved
May 2023
CL/23/02317
21 Silchester Road, London, W10 6sf
Rear extension
Approved
Apr 2023
PP/23/01497
88 Sirdar Road, London, W11 4eg
Loft or dormer
Approved
Apr 2023
PP/23/01167
7 Darnley Terrace, London, W11 4rl
Loft or dormer
Withdrawn
Jun 2023
CL/23/00982
66, Macfarlane Road, W12 7jz
Other householder work
Approved
May 2023
2023/00174/CLE
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%
8 weeks
Basement
–
–
83%
9 weeks
Porch or front extension
–
–
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.