What you could build at TW1 4SD: 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 Strawberry Hill, Richmond upon Thames.
50extensions seen within 600 m in the last 10 years
4loft conversions within 600 m in the last 10 years
98.2extensions 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 Strawberry Hill.
Move to a home 20 m² bigger (about £862,000)
Stamp duty on the new home
£33,100
Estate agent on yours 1.2% + VAT
£10,512
Solicitors, buying and selling
£3,000
Survey
£600
Removals
£1,500
Money gone
£48,712
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
−£79,200
Money gone
−£21,700
On these figures, extending loses about £70,412 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.
48, Tower Road, Tw1 4pe
Rear extension
Under consideration
–
PA26/1387
1, Michelham Gardens, Tw1 4sd
Garage conversion or garage
Under consideration
–
PA26/1264
22, Michelham Gardens, Tw1 4sb
Loft or dormer
Under consideration
–
PA26/1339
39, Upper Grotto Road, Tw1 4ng
Rear extension
Approved
Apr 2026
PA26/0529
26, Strawberry Hill Road, Tw1 4pu
Basement
Approved
May 2026
PA26/0405
42, Bonser Road, Tw1 4rg
Loft or dormer
Approved
Mar 2026
PA26/0406
3, Cross Deep Gardens, Tw1 4qz
Rear extension
Approved
Feb 2026
PA25/4446
17, Michelham Gardens, Tw1 4sd
Rear extension
Approved
Feb 2026
PA25/4449
17, Strawberry Vale, Tw1 4rx
Porch or front extension
Approved
Jan 2026
PA25/4293
25, Tower Road, Tw1 4pj
Outbuilding or garden room
Approved
Mar 2026
PA25/4242
21, Holmes Road, Tw1 4rf
Side return or wrap-around
Approved
Dec 2025
PA25/4016
257, Waldegrave Road, Tw1 4sy
Garage conversion or garage
Under consideration
–
PA25/2511
26, Strawberry Hill Road, Tw1 4pu
Basement
Approved
–
PA25/3691
19, Waldegrave Gardens, Tw1 4pq
Other householder work
Approved
Dec 2025
PA25/3527
77, Strawberry Vale, Tw1 4sj
Loft or dormer
Other
Dec 2025
PA25/3359
6, Hawkesley Close, Tw1 4tr
Basement
Other
Nov 2025
PA25/3296
40, Orford Gardens, Tw1 4pl
Rear extension
Approved
Oct 2025
PA25/2980
2, Holmes Road, Tw1 4re
Outbuilding or garden room
Approved
Sept 2025
PA25/2607
27, Clive Road, Tw1 4sq
Loft or dormer
Approved
Sept 2025
PA25/2588
21, 21 Holmes Road, 21 , Tw1 4re
Loft or dormer
Other
Sept 2025
PA25/2488
17, Strawberry Vale, Tw1 4rx
Windows, doors or cladding
Approved
Sept 2025
PA25/2345
73, Popes Grove, Tw1 4jt
Other householder work
Approved
Sept 2025
PA25/1955
265, Waldegrave Road, Tw1 4su
Two-storey extension
Approved
Aug 2025
PA25/2182
12, Strawberry Hill Road, Tw1 4pt
Other householder work
Approved
Jul 2025
PA25/1958
297, Waldegrave Road, Tw1 4su
Rear extension
Approved
Jul 2025
PA25/1746
11, Tower Road, Tw1 4pd
Loft or dormer
Approved
Jun 2025
PA25/1065
265, Waldegrave Road, Tw1 4su
Loft or dormer
Other
May 2025
PA25/0771
35, Clive Road, Tw1 4sq
Loft or dormer
Approved
May 2025
PA25/0718
27, Clive Road, Tw1 4sq
Rear extension
Under consideration
–
25/0215/PS192
39, Popes Grove, Tw1 4jz
Other householder work
Under consideration
–
24/3115/HOT
45, Cross Deep Gardens, Tw1 4qz
Rear extension
Under consideration
–
25/0107/HOT
265, Waldegrave Road, Tw1 4su
Loft or dormer
Under consideration
–
24/2863/HOT
28, Waldegrave Gardens, Tw1 4ph
Side extension
Under consideration
–
24/3145/HOT
1, Tower Road, Tw1 4pd
Two-storey extension
Under consideration
–
24/3070/HOT
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.