House Extensions · KT3 New Malden
Kingston upon Thames applies standard suburban householder control across New Malden, a settled inter-war family market with few conservation constraints and a large Korean community.
If your property sits elsewhere in the borough, the borough-wide page for house extensions in Kingston upon Thames covers the same service across every ward.
House extensions in New Malden are dominated by single-storey rear and side-return additions on KT3's inter-war bay-fronted semis and terraces around new, with double-storey and wrap-around schemes where the plot allows. Kingston Council weighs depth, height and neighbour daylight; many extensions across New Malden, Motspur Park fringe, Coombe fringe, Old Malden fringe are Permitted Development, which we confirm with a Lawful Development Certificate before you build.
The whole spectrum — rear extensions, side returns, wraparounds, double-storey, basement digs. Planning-led design with detailed technical phase, ideal for inter-war bay-fronted semis and terraces around new typical of New Malden.
Across New Malden, Motspur Park fringe, Coombe fringe, Old Malden fringe in KT3, the dominant property is inter-war bay-fronted semis and terraces around new malden, with some edwardian and post-war infill. That stock shapes what house extension drawings looks like here: the right approach for a period terrace differs from a mansion-block flat or a new-build, and Kingston Council judges each on design quality and neighbour impact. We survey the specific New Malden property, confirm the planning route — Permitted Development, a Lawful Development Certificate, or full planning — and draw a council-ready set tailored to the KT3 streetscape.
Housing stock in KT3: Inter-war bay-fronted semis and terraces around New Malden, with some Edwardian and post-war infill.
Within the district: New Malden, Motspur Park fringe, Coombe fringe, Old Malden fringe.
Streets we know in KT3: the Coombe Road area, the streets around New Malden High Street and the inter-war roads toward Motspur Park. Each road has its own building line, boundary treatment and precedent that Kingston Council weighs when assessing a house extension drawings scheme.
Getting around KT3: New Malden and Motspur Park on South Western Railway.
Property values: for houses rather than all property, Kingston's medians last year were £570,000 terraced, £774,089 semi-detached and £1,087,500 detached. The KT3 figure of £650,000, taken across every type of home sold, sits between the first two. Contains HM Land Registry data (c) Crown copyright and database right 2026
Borough character: Outer south-west London suburban; generally permissive; riverside conservation areas add character in Kingston town.
Measured existing survey, photographic record, Article 4 and conservation check specific to New Malden before we quote.
2–3 design options at concept stage — alternative layouts, glazing, roof forms.
Site location plan, existing and proposed plans, elevations, sections, D&AS where required.
Part L thermal, Part B fire, Part M accessibility, structural strategy.
Steel beam, foundation, lintel design. Chartered engineer sign-off.
Party Wall notices where needed; Thames Water Build Over Agreement where within 3m of a public sewer.
Single planning or building-regs submission.
Planning + building regs + structural.
Listed, conservation or complex sites.
Because KT3 is a settled family suburb of inter-war bay-fronted semis — ideal for rear and side extensions and hip-to-gable loft conversions as families grow. With few conservation constraints, much of the work runs on the Permitted Development route, which we confirm with a Lawful Development Certificate.
Usually yes on the semis — a hip-to-gable plus rear dormer within the 50 cubic metre volume allowance, confirmed by a Lawful Development Certificate. We check the roof head height and draw the scheme for Building Control too, which is essential for the new floor and stair.
Often, on the wider semi plots — a wrap-around ground-floor extension or a two-storey side addition, subject to Kingston's design and neighbour-amenity policy on the 45-degree test. We design within those limits and produce the planning and Building Regulations drawings together.
New Malden offers strong value for south-west London families.
Kingston Council charges its own statutory application fee (currently £548 for a householder planning application, £610 for a full application). We quote the drawings as one fixed price and the free site survey covers every KT3 address.
For a KT3 project across New Malden, Motspur Park fringe, Coombe fringe, Old Malden fringe, 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 Kingston Council (8 weeks for a householder application). We carry the New Malden application through every officer query to the decision.
New Malden (KT3) sits primarily in Kingston upon Thames, so applications are decided by Kingston Council. We confirm the planning route for your exact address before quoting.
Almost always. Any structural work behind house extension drawings in New Malden — 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 Kingston Council Building Control or an approved inspector. On KT3'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. 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 KT3 homes.
Working across a borough boundary, or unsure which council will decide your application? Every service we offer is listed for KT1, KT2, KT5 and KT6.
Pick a slot that suits you. No obligation and no sales pressure, just straight answers on your planning route.
Every KT3 postcode district we draw in, the stock that dominates it and the authority that validates a house extension there. KT3 fees below are the statutory England rates for 2026, not house extension estimates.
| Postcode | Area | Dominant stock | What it means for a house extension |
|---|---|---|---|
| KT3 | New Malden | Edwardian villas, 1930s semi-detached | New Malden sits wholly inside KT3, so Kingston Council validates every house extension submitted from an KT3 address. |
| KT3 | Coombe | 1930s detached, Edwardian villas | Coombe sits inside KT3; house extension proposals here are determined by Kingston Council. |
| KT1 | Kingston upon Thames | Georgian fragments, Victorian terraces, 1930s semi-detached | Adjoining district to KT3, also inside Kingston upon Thames for house extension purposes. |
| KT2 | Kingston / Norbiton | Georgian fragments, Victorian terraces, 1930s semi-detached | Adjoining district to KT3, also inside Kingston upon Thames for house extension purposes. |
| KT5 | Surbiton / Tolworth | Edwardian villas, mansion blocks | Adjoining district to KT3, also inside Kingston upon Thames for house extension purposes. |
Roof pitch, wall build-up and plot depth change every few KT3 streets, and each one changes what a house extension can achieve at that address.
KT3 (New Malden) conservation designations: there are 22 across Kingston Council, Hampton Wick, Coombe Hill, Kingston Old Town among them. Designation costs a KT3 (New Malden) owner the permitted-development route: a house extension then needs a £548 householder application over 8 weeks, in place of the £249 prior approval route that takes 6 weeks. Hampton Wick is the KT3 (New Malden) designation that most often changes a house extension design.
Article 4 and your KT3 (New Malden) house extension: Kingston Council has made no borough-wide direction, so permitted development for a house extension in KT3 (New Malden) generally survives outside KT3 (New Malden) conservation areas and listed curtilages. A Lawful Development Certificate at £274 is how a KT3 owner records that a house extension was lawful.
KT3 (New Malden) housing stock: Edwardian villas in Surbiton and New Malden; Victorian terraces in Kingston central; 1930s semi-detached in Chessington and Tolworth; post-war in New Malden. Outer south-west London suburban; generally permissive; riverside conservation areas add character in Kingston town. Read that before choosing a house extension route in KT3 (New Malden) — construction, not postcode, sets what is achievable. Kingston Council charges £548 for a householder application and has 8 weeks to determine it.
Sources for this KT3 house extension 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.
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