Basement Conversions · TW9 Richmond
Fixed-fee basement conversion drawings for Richmond, Kew, Kew Gardens, North Sheen in the TW9 postcode, drawn by an MCIAT-chartered architectural technologist and submitted to Richmond Council. Richmond upon Thames applies some of London's tightest householder and conservation control around Kew Green, Kew Gardens and Central Richmond, with the Royal Botanic Gardens a UNESCO World Heritage Site nearby.
MCIAT chartered drawings for planning, building regs, lofts and extensions — fixed fees 30% below typical London architects. Tell us what you need and we’ll reply the same working day.
Basement conversions and lowering existing cellars in Richmond add space without touching the roofline — valuable on TW9's period houses around Richmond, Kew, Kew Gardens, North Sheen. Richmond Council reviews structural, drainage and flood-risk impact, and a Party Wall award plus a Thames Water build-over agreement are usually required. We coordinate the structural engineer and the waterproofing design.
Full architectural technology service for basement digs and cellar conversions in Richmond — structural underpinning design, waterproofing strategy, Party Wall coordination, planning where required, and building regulations through to completion certificate.
Across Richmond, Kew, Kew Gardens, North Sheen in TW9, the dominant property is victorian and georgian terraces and villas around richmond and kew, riverside houses, and mansion flats — a premium river market. That stock shapes what basement conversion drawings looks like here: the right approach for a period terrace differs from a mansion-block flat or a new-build, and Richmond Council judges each on design quality and neighbour impact. We survey the specific Richmond property, confirm the planning route — Permitted Development, a Lawful Development Certificate, or full planning — and draw a council-ready set tailored to the TW9 streetscape.
Housing stock in TW9: Victorian and Georgian terraces and villas around Richmond and Kew, riverside houses, and mansion flats — a premium river market.
Within the district: Richmond, Kew, Kew Gardens, North Sheen.
Streets we know in TW9: the Kew Green and Kew Gardens roads, Richmond Green and the streets around the Royal Botanic Gardens. Each road has its own building line, boundary treatment and precedent that Richmond Council weighs when assessing a basement conversion drawings scheme.
Conservation areas: Kew Green, Kew Gardens, Central Richmond, Richmond Green. Inside these, most external work needs full planning and a Heritage Statement.
Getting around TW9: Richmond and Kew Gardens on the District line and Overground, plus South Western Railway and Kew Bridge.
Property values: around £500,000 for a flat and £900,000-£1.6m for a house — a useful gauge of the build value an extension or loft adds in TW9.
Borough character: Highest conservation area coverage in London; Royal Parks and Thames corridor add heritage layers; design quality heavily scrutinised.
Desktop study plus measured survey assessing existing foundations, ground conditions, water table level and underpinning viability for your Richmond property.
New-build basements and lightwell extensions need planning permission. Cellar conversions of existing space are usually Permitted Development. We confirm the route and submit where needed.
Underpinning sequence drawings, reinforced concrete design, temporary works strategy — all to Eurocode with chartered engineer sign-off.
BS 8102:2022 compliant — cavity drain, cementitious tanking or membrane system specified for Richmond's ground conditions and water table.
Full Plans application to Richmond Council Building Control or an approved inspector covering structure (Part A), fire safety (Part B), damp-proofing (Part C), ventilation (Part F) and thermal performance (Part L).
Almost every Richmond basement triggers Party Wall notices. We also manage Thames Water Build Over Agreements where within 3m of a public sewer.
Single planning or building-regs submission.
Planning + building regs + structural.
Listed, conservation or complex sites.
Yes, but most of TW9 sits in the Kew Green, Kew Gardens, Central Richmond or Richmond Green conservation areas, where rear and side extensions and roof changes need full planning with a Heritage Statement rather than Permitted Development. Proximity to the UNESCO World Heritage Site at Kew also raises the bar. We design to the period and submit to Richmond.
Very. The Kew Gardens and Kew Green conservation areas protect the Victorian and Georgian character, and the council resists changes that harm the setting of the Royal Botanic Gardens World Heritage Site. We produce a careful Heritage Statement and design within those constraints for a realistic chance of consent.
Rarely — most TW9 houses are in conservation areas where Permitted Development for roof changes is removed, so a dormer needs full planning and conservation rooflights are often preferred to the street side. We confirm the designation for your road and design the scheme to suit.
With TW9 houses commonly £900,000-£1.6m, a well-designed and consented extension or loft adds substantial value and family space in one of London's most desirable river markets. The planning bar is high, so professional drawings and a strong Heritage Statement matter — and our fixed fee keeps the cost predictable.
Our fixed fee for basement conversion drawings in Richmond starts at £1,950 — no hourly billing. With Richmond property at around £500,000 for a flat and £900,000-£1.6m for a house, the professional drawing fee is a small fraction of the value the work adds to TW9's victorian and georgian terraces and villas around. Richmond Council charges its own statutory application fee on top (currently £258 for a householder planning application, £578 for a full application). We quote the drawings as one fixed price and the free site survey covers every TW9 address.
For a TW9 project across Richmond, Kew, Kew Gardens, North Sheen, expect roughly 3–4 weeks from instruction to submission: week 1 the measured survey, weeks 2–3 the drawings and your revisions, then validation and the statutory determination by Richmond Council (8 weeks for a householder application). We carry the Richmond application through every officer query to the decision.
Richmond (TW9) sits primarily in Richmond upon Thames, so applications are decided by Richmond Council. Article 4 in force in the borough: No. Conservation areas within TW9 include Kew Green, Kew Gardens, Central Richmond, Richmond Green, where full planning and a Heritage Statement are required. We confirm the planning route for your exact address before quoting.
Almost always. Any structural work behind basement conversion drawings in Richmond — new openings, steel beams, loft floors, foundations — needs Building Regulations approval covering structure (Part A), fire escape (Part B) and insulation (Part L), submitted to Richmond Council Building Control or an approved inspector. On TW9's typically terraced and semi-detached stock, a Party Wall notice to adjoining neighbours is normally required before the steelwork. We coordinate both as part of the Complete package.
In value terms, yes. With Richmond (TW9) property at around £500,000 for a flat and £900,000-£1.6m for a house, a well-designed extension or loft typically returns more than it costs in added floor area and sale value, while our fixed drawing fee from £1,950 keeps the professional cost predictable. The bigger risk is an unapproved or non-compliant scheme — which is why council-ready drawings and a clean Building Control sign-off matter on TW9 homes.
From £840.
From £840.
From £1,225.
From £1,225.
From £1,575.
From £995.
From £350.
From £540.
From £450.
From £1,225.
Pick a slot that suits you. No obligation and no sales pressure — just straight answers on your planning route, fixed fee and timescale.
Every TW9 postcode district we draw in, the stock that dominates it and the authority that validates a basement conversion there. TW9 fees below are the statutory England rates for 2026, not basement conversion estimates.
| Postcode | Area | Dominant stock | What it means for a basement conversion |
|---|---|---|---|
| TW9 | Richmond / Kew | Georgian terraces, Victorian villas | Richmond / Kew sits wholly inside TW9, so Richmond Council validates every basement conversion submitted from an TW9 address. |
| TW9 | Richmond | Georgian terraces, Victorian villas | Richmond sits inside TW9; basement conversion proposals here are determined by Richmond Council. |
| TW9 | Kew | Georgian and Edwardian villas | Kew sits inside TW9; basement conversion proposals here are determined by Richmond Council. |
| SW13 | Barnes | Georgian villas, Edwardian terraces | Adjoining district to TW9, also inside Richmond upon Thames for basement conversion purposes. |
| SW14 | Mortlake / East Sheen | Edwardian villas, 1930s semi-detached | Adjoining district to TW9, also inside Richmond upon Thames for basement conversion purposes. |
| TW1 | Twickenham | Georgian fragments, Victorian terraces, Edwardian villas | Adjoining district to TW9, also inside Richmond upon Thames for basement conversion purposes. |
| TW2 | Twickenham / Whitton | Georgian fragments, Victorian terraces, Edwardian villas | Adjoining district to TW9, also inside Richmond upon Thames for basement conversion purposes. |
Roof pitch, wall build-up and plot depth change every few TW9 streets, and each one changes what a basement conversion can achieve at that address.
Conservation areas covering TW9 (Richmond / Kew): Richmond Council runs 72, and Richmond Green, Kew Green, Hampton Wick are the ones TW9 (Richmond / Kew) owners meet most. A basement conversion inside a TW9 (Richmond / Kew) conservation area loses permitted development, so the TW9 (Richmond / Kew) submission is a householder application at £258 decided in 8 weeks — not a £120 prior approval decided in 6 weeks. In Hampton Wick a basement conversion is judged on the street elevation first.
No blanket Article 4 over TW9 (Richmond / Kew): Richmond Council has not withdrawn permitted development across TW9 (Richmond / Kew), so a basement conversion outside a TW9 (Richmond / Kew) conservation area usually keeps it. The £129 Lawful Development Certificate is still the document a TW9 owner wants on file.
TW9 (Richmond / Kew) housing stock: Georgian in Richmond Green and Twickenham; Edwardian villas in Barnes and East Sheen; 1930s semi-detached in Whitton; riverside cottages along the Thames. Highest conservation area coverage in London; Royal Parks and Thames corridor add heritage layers; design quality heavily scrutinised. Read that before choosing a basement conversion route in TW9 (Richmond / Kew) — construction, not postcode, sets what is achievable. Basement conversions in TW9 (Richmond / Kew) start at £1,950 on a fixed fee, or £1,750 for the Complete package covering both Richmond Council submissions.
Sources for this TW9 basement conversion page: borough policies maps and conservation-area registers (2025–26), Royal Mail postcode district boundaries, the Town and Country Planning (Fees for Applications) (England) Regulations, the Town and Country Planning (General Permitted Development) (England) Order 2015 as amended, and the Party Wall etc. Act 1996.
Free fixed quote in 60 seconds. From £1,950. MCIAT chartered.
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