Drawings that turn a Sevenoaks house into self-contained flats — units sized to space standards, separated for sound and fire, and drawn to Sevenoaks District Council's conversion policy so the change of use is approved, delivered in days and revised free until your decision, with a free feasibility check first.
Sevenoaks District Council granted 87% of the householder planning decisions it made in its latest published year — level with the 87% England-wide householder average. Around 93% of the district is Metropolitan Green Belt, one of the most green-belt-constrained districts in England, so most countryside development faces a very-special-circumstances test, which is where a policy-literate drawing pack earns its keep. Its dominant Georgian (1714–1837), Victorian (1837–1901), Edwardian (1901–1910), interwar (1918–1939) and postwar (1945–1970) housing stock sets the design brief on most streets.
Before permission is required, Class B allows 40m³ of added loft volume on a terrace and 50m³ on a semi or detached house, and Class A allows a 3m single-storey rear extension on a terrace or 4m on a detached house. Sevenoaks carries at least one Article 4 direction, and conservation areas including Sevenoaks High Street, The Vine and Sevenoaks Weald remove those rights outright, so we confirm your exact address before a line is drawn. A validated householder application in Sevenoaks is determined against an 8-week statutory target.
Sevenoaks (the historic market-town core around the High Street and The Vine, with a Georgian and Victorian townscape), Westerham (a historic market town with a conservation-area centre), Kemsing (a downland village where front gardens and boundaries are controlled by an Article 4 direction), Otford (a historic green-belt village of vernacular cottages around the pond), Edenbridge (a small town on the district's southern High Weald edge) and Swanley (a denser, more suburban postwar settlement to the north) — these are the Sevenoaks pockets our drawings cover most. Heritage designations here include Sevenoaks High Street, The Vine, Sevenoaks Weald, Hartslands, Westerham and Kemsing. Sevenoaks District Council weighs each proposal against the Sevenoaks Core Strategy (adopted February 2011) and the Allocations and Development Management Plan (adopted February 2015), where over half the district lies within the Kent Downs or High Weald National Landscapes (AONBs), where landscape protection shapes design and siting. Converted flats and maisonettes appear around Sevenoaks town and Swanley, and none of them hold householder permitted-development rights.. On roofs the borough is dual-pitch tiled roofs on the town villas and terraces and steep tiled and hipped roofs on the vernacular village cottages, over Victorian and Edwardian villas and terraces around Sevenoaks town, interwar and postwar detached and semi-detached commuter housing, historic vernacular cottages in Kentish ragstone, weatherboarding and tile-hanging across the green-belt and AONB villages and larger country properties in the rural south.
Splitting one dwelling into several is the most policy-heavy job a house takes on, and Sevenoaks has the stock that invites it — the borough's Victorian and Edwardian villas and terraces around Sevenoaks town, interwar and postwar detached and semi-detached commuter housing, historic vernacular cottages in Kentish ragstone, weatherboarding and tile-hanging across the green-belt and AONB villages and larger country properties in the rural south include the large period houses and mansion-block flats that convert well, and streets already part-converted set the pattern. But because you are creating new homes, Sevenoaks District Council assesses the scheme against its housing and conversion policies, not just its extension guidance, so the internal layout carries planning weight it never would in a single house.
The layout has to satisfy several standards together. Each flat must meet the nationally described space standard for its number of bedrooms and bed spaces, with adequate light and outlook; the mix the council will accept is often set by policy, with some boroughs resisting too many small units or requiring a family-sized flat; and every unit needs its own amenity, plus cycle and refuse storage that works for the whole building. Around 93% of the district is Metropolitan Green Belt, one of the most green-belt-constrained districts in England, so most countryside development faces a very-special-circumstances test, which shapes what mix and layout will pass here.
Where the house sits in a conservation area — Sevenoaks High Street, The Vine, Sevenoaks Weald, Hartslands, Westerham and Kemsing among Sevenoaks's — external changes are read hard: new entrances, bin and bike stores, meter boxes and any subdivision visible from the street all have to respect the area's character. The Kemsing conservation area Article 4 direction (adopted 2023) brings the loss or alteration of front boundary treatments and front gardens under planning control, and the district's many conservation areas such as Westerham and the Sevenoaks High Street layer further restrictions on external changes. We resolve the frontage and access before the internal layout is fixed.
Yes — a house-to-flats conversion is a change of use and always needs a full application to Sevenoaks District Council. The scheme has to satisfy each of these, and the drawings are where each is proven:
We lay out flats that meet the space standard, plan the sound and fire separation, and solve the entrances, bins and bike stores — then draw the change-of-use application to Sevenoaks District Council's conversion policy so the scheme is judged on a complete proposal, not bounced for a unit that is too small or a layout that cannot be separated.
Below is Sevenoaks District Council's real householder and residential decision record, drawn from official planning statistics and refreshed as new data lands. Sevenoaks grants a fair share of applications broadly in line with the national picture, with pervasive Green Belt and AONB coverage the defining pressure on anything beyond modest householder work. Conversions are judged harder than extensions because they create new homes, so a scheme that proves space, mix and separation upfront is decided far more smoothly than one that leaves the officer to find the gaps.
Source: MHCLG planning application statistics (householder decisions, England, 1 April 2025 - 31 March 2026). Compare every borough on our London approval-rate league table.
Tell us about your project and get a fixed, no-obligation quote back within one working day. If you don't need planning permission at all, we'll tell you that too — for free.
The conversions that pass in Sevenoaks are the ones that treat the new homes as homes, not as the maximum number of doors that fit. Across Sevenoaks, Westerham and Kemsing, the approved schemes give each flat a proper layout at or above the space standard, a sensible mix rather than a stack of studios, and amenity, bin and cycle provision that does not wreck the frontage. Overcrowding the building is the quickest route to refusal, and it rarely adds the value it promises.
Over half the district lies within the Kent Downs or High Weald National Landscapes (AONBs), where landscape protection shapes design and siting. We design the mix to what Sevenoaks District Council will accept, prove each unit meets the standard on the plan, and coordinate the planning layout with the sound and fire separation from the outset — so the scheme that gets permission is the same one building control can sign off, not a layout that has to be torn up at the next stage.
We convert houses and reconfigure flats on the period streets and mansion blocks across the borough. A few of the Sevenoaks neighbourhoods where conversions come up most often:
Flat conversion drawings for Sevenoaks's the historic market-town core around the High Street and The Vine, with a Georgian and Victorian townscape — space-standard checked, separation-planned and drawn to Sevenoaks District Council's conversion policy.
Flat conversion drawings for Westerham's a historic market town with a conservation-area centre — space-standard checked, separation-planned and drawn to Sevenoaks District Council's conversion policy.
Flat conversion drawings for Kemsing's a downland village where front gardens and boundaries are controlled by an Article 4 direction — space-standard checked, separation-planned and drawn to Sevenoaks District Council's conversion policy.
Flat conversion drawings for Otford's a historic green-belt village of vernacular cottages around the pond — space-standard checked, separation-planned and drawn to Sevenoaks District Council's conversion policy.
Flat conversion drawings for Edenbridge's a small town on the district's southern High Weald edge — space-standard checked, separation-planned and drawn to Sevenoaks District Council's conversion policy.
Flat conversion drawings for Swanley's a denser, more suburban postwar settlement to the north — space-standard checked, separation-planned and drawn to Sevenoaks District Council's conversion policy.
A conversion is judged on planning and building standards together. This is what each requires and who checks it.
| Requirement | What it means | Set by | Checked at |
|---|---|---|---|
| Change of use | Creating separate self-contained units | Planning policy | Sevenoaks District Council planning |
| Space standards | Minimum floor area per bedroom and bed space | National space standard | Sevenoaks District Council planning |
| Unit mix & amenity | Sensible flat sizes, light, outdoor space | Local housing policy | Sevenoaks District Council planning |
| Sound & fire separation | Part E acoustic and protected escape | Building regulations | Building control |
In conservation areas such as Sevenoaks High Street and The Vine, external changes to a Sevenoaks conversion — entrances, bin and bike stores — are assessed against the area's character.
A fixed process built around how Sevenoaks District Council judges conversions — most drawing sets are submission-ready within seven days of survey.
Send us your Sevenoaks postcode and the building. We test how many units realistically fit at the space standard, confirm the mix Sevenoaks District Council is likely to accept, and flag conservation, Article 4 and access constraints before you commit.
We measure the building accurately, because a conversion lives or dies on floor areas — every flat has to be proven against the space standard on a plan that matches the real property.
We design the flats to the space standard, coordinate the sound and fire separation and the entrances, bins and cycle stores, and draw the full change-of-use application to Sevenoaks District Council's conversion policy.
We lodge the application, manage validation and case-officer queries, and revise the drawings free until Sevenoaks District Council issues its decision.
Always. Splitting one house into two or more self-contained flats is a change of use, which is never permitted development, so a full application to Sevenoaks District Council is required. The council assesses the unit sizes, the mix and the amenity against its housing policy, as well as any external changes. A Sevenoaks conversion is judged more closely than an extension precisely because it creates new homes.
Each flat must meet the nationally described space standard, which sets a minimum floor area by the number of bedrooms and bed spaces — a one-bed one-person flat starts at 37–39 square metres, and larger units scale up from there. Sevenoaks District Council will refuse units below the standard. We test how many compliant flats a Sevenoaks building genuinely holds at feasibility, rather than drawing undersized units that cannot be approved.
Once you create separate units, building control requires Part E acoustic separation between them — the floors and party walls must be built or upgraded to resist airborne and impact sound — and a protected means of escape so each flat can be left safely in a fire. These are checked by Sevenoaks District Council's building control, separately from planning. We plan the separation into the layout from the start, so the planning design and the building-regs build are the same scheme.
Not necessarily. Many boroughs set policy on the mix — resisting schemes that are all studios or one-beds, and sometimes requiring a family-sized flat — to keep a range of homes. Sevenoaks District Council applies its own housing policy to a conversion, so the profitable-looking stack of small units is often the one that gets refused. We design the mix to what the borough will actually accept before drawing the application.
Usually yes. Once the Sevenoaks building is flats, each unit is normally sold or let on a lease, and a Land Registry-compliant lease plan is needed to define its extent. The measured survey behind the conversion drawings is the ideal base for those lease plans, so the same accurate record serves the planning application, the building-regs layout and the leases without measuring the building twice. Sevenoaks District Council is the decision-maker.
We price each Sevenoaks conversion on the number of units and the building's size and complexity, and send a fixed, no-obligation quote within one working day. It covers the feasibility, the change-of-use application drawings and free revisions until Sevenoaks District Council decides. Building-regs separation drawings and any council fee are quoted separately. Call 020 7864 7245 to start.
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