Area guide · TW9 & TW10
House Extensions in Richmond (TW9 & TW10)
Thinking about extending a Richmond house? Then you already know the tension at the heart of it. This is a town of Georgian townhouses and substantial Victorian villas, wrapped in conservation areas that cover much of its centre, and watched over by a panorama from Richmond Hill so valued that Parliament passed an Act to protect it. Heritage sensitivity is the defining planning layer in TW9 and TW10, and it shapes every brief we take on here. The projects themselves sit at the top of our range: whole-house programmes, double-storey schemes near the Richmond Park edge, and above all basements, because a tight townhouse plot with nowhere to spread outward can still grow downward. Whatever the scale, one free design visit produces one fixed, itemised figure.
Live planning data
What wins approval in a town this protected
Richmond upon Thames guards its townscape as closely as any authority we work with, and the officers' first question never changes: does this proposal respect the character around it? Treat that as a brief rather than a barrier. Schemes drawn with correct proportion, honest materials and a clear account of their heritage context move through the system, while off-the-peg designs stall. We prepare every application as a design argument, the same method behind our luxury extensions service, and we manage planning end to end so you never chase a consultation or a committee date yourself.
Two local specifics deserve attention before pen touches paper. Conservation designation removes some permitted development rights, so a route that works elsewhere may simply not exist on your street. And anything that could touch the foreground of the protected Richmond Hill panorama attracts an extra layer of scrutiny. Neither stops good work; both reward preparation.
Each proposal is judged on its own merits, and we build the case before the drawings go anywhere near the council.
Local knowledge
The streets and the stock
Richmond Hill. The houses climbing the hill are the town's calling card, and extending them is precision work: rear additions composed to conservation expectations, and basements that add a whole floor without changing what the street or the protected view sees.
The Richmond Park edge. The roads along the Park boundary carry the biggest houses in town, and the briefs match: double-storey reworks, leisure basements and whole-house programmes that reorganise a large villa around the way a family actually lives.
The Queens Road side. Substantial Victorian villas on more generous plots, where a wide glazed rear, a reworked ground floor or a two-storey addition suits the scale of the original architecture.
The Georgian townhouses. Four storeys, no side access, a courtyard garden: the classic central Richmond plot. When outward growth is impossible the answer sits below ground, and a well-engineered basement gives these houses the kitchen, utility and media space the upper floors cannot.
Every street is different. That's the point.
We design to Richmond's stock and to what the council demonstrably approves — not to a template. A free site visit tells you what your house can take.
Get my free estimateHonest numbers
What an extension costs in Richmond in 2026
Richmond pricing reflects both the specification owners expect and the care heritage streets demand. The ranges below are all-in build figures before VAT, professional fees and kitchen fit-out:
| Extension type | Typical Richmond cost | On-site time | Usual planning route |
|---|---|---|---|
| Side-return extension | £50,000 to £95,000 | 2 to 3 months | PD only outside conservation areas |
| Single-storey rear | £60,000 to £125,000 | 3 to 4 months | Full application on most central streets |
| Kitchen extension (incl. mid-range kitchen) | £75,000 to £150,000 | 3 to 4 months | As above |
| Loft conversion with dormer | £70,000 to £120,000 | 6 to 10 weeks | Usually permitted development |
| Double-storey rework | £105,000 to £230,000 | 5 to 7 months | Full application |
| Basement floor | Priced on design | 6 to 12 months | Full application |
Work to £3,500 to £5,500 per square metre across TW9 and TW10. For how the larger budgets divide between structure, glazing and finish, read the luxury extension cost guide. Quotes follow a free design visit and arrive fixed and itemised, so the number you sign is the number you pay.
Permissions, handled
Planning around the view
Conservation first. We check your street's designation before sketching anything, because it decides whether permitted development survives and how the design case must be framed.
The protected panorama. An Act of Parliament shields the view from Richmond Hill, and proposals within its sweep get examined accordingly. Massing and rooflines are shaped with that in mind from the first drawing.
Where PD applies, we prove it. On streets that keep their rights we secure a Lawful Development Certificate, putting the lawful status of the work on paper rather than on trust.
Timescales and neighbours. Householder decisions run to roughly eight weeks. Basements and boundary excavation bring the Party Wall Act into play; allow £1,000 to £2,500 per affected neighbour where surveyors are appointed, with notices handled by us.
How it works
How it works
- Free design visit. We walk the house, read the designations on your street and give you a straight view on scope and budget.
- Design and drawings. A scheme composed for your architecture and the heritage case it must make.
- Planning, managed. Application, consultations and any heritage questions carried through to the decision notice.
- Fixed-price build. One itemised figure, one accountable team, building control signed off at the end.
Questions, answered
Richmond extension FAQs
Do I need planning permission in a Richmond conservation area?
Almost always, yes. Conservation designation strips out most of the permitted development rights that cover rear extensions elsewhere, so expect a full householder application, prepared and managed by us as standard.
Is a basement realistic under a Richmond townhouse?
Frequently it is the best option available. Central plots rarely have room to extend outward, and a basement adds an entire storey with no change to the street elevation. Expect a full application, serious structural engineering and careful party wall management, all priced on design.
How does the protected view affect my project?
If your roofline or massing sits within the protected sweep from the Hill, the council will look closely at it. Most domestic schemes fall well below the threshold of harm, but we model the impact early rather than discover it at committee.
What should I budget?
Plan on £3,500 to £5,500 per square metre in 2026. A single-storey rear typically runs £60,000 to £125,000, a double-storey rework £105,000 to £230,000, and basements sit past £250,000 in most cases, priced on design. All figures exclude VAT and fees.
How long will the council take?
Around eight weeks for a standard householder decision once the application is validated. Heritage input can stretch that, which is why we front-load the design case instead of answering objections later.
Do you run the whole project?
Yes. Design, planning, structural coordination, party wall notices and the build itself sit with one team from first visit to final sign-off.
Nearby areas we cover
What clients say
Rated 5.0 on Google
“Used The Extension Company for a loft conversion on our semi detached in Barnet and couldn't be happier. They explained what was possible at the first visit, sorted the planning side, and gave a fixed price with no surprises at the end.…” read the full review
“Really impressed with the entire project. The side extension and conservatory have been finished to a very high standard and the team made the process straight forward and stress-free. It’s transformed the space and added so much value, would definitely recommend.”
“Brilliant experience with the extension company, transparent from the word go. Completed a double story extension for me and I couldn’t be more pleased. Thank you”
“I got the extension company to do a bathroom refurb for us a January they done a great job they managed to fit in a large shower as well as a bath”
Reviews shown word for word from our Google profile. Read all 8 reviews on Google
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Free site visit anywhere in Richmond, honest feasibility advice and a fixed, itemised price — design, planning and build handled end to end by the Pine Grove team.
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