Single-storey, double-storey, rear and side extension drawings for Sevenoaks homes — measured to Sevenoaks District Council's design guidance, delivered in days and revised free until your decision, with a free approval-odds check before you commit.
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.
Sevenoaks homes come in a handful of recurring shapes, and each one points to a different extension. The borough is built largely from 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, so a Victorian terrace usually wants a rear or side-return infill, while an interwar semi has room for a wider single-storey wrap or a two-storey side addition. Sevenoaks District Council judges every one of them against the Sevenoaks Core Strategy (adopted February 2011) and the Allocations and Development Management Plan (adopted February 2015), weighing footprint, height and the impact on the house next door before it looks at the elevations.
That is why the drawings decide the outcome. We set the extension depth against the permitted-development limits precisely, keep the eaves and ridge within the allowances, and plot the 45-degree daylight lines to the neighbours' windows so the case officer can see the amenity test is passed. 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, so we design around it from the first sketch rather than discover it at validation.
Sevenoaks also protects whole streets — Sevenoaks High Street, The Vine, Sevenoaks Weald, Hartslands, Westerham and Kemsing among them. 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. On designated land the larger-home extension route and most side extensions stop being permitted development, so we confirm your address against those layers before drawing a line.
Plenty of Sevenoaks extensions are permitted development and need no planning application — a single-storey rear extension within the depth and height limits is the common case. You will normally need to apply to Sevenoaks District Council if any of these apply:
We draw the footprint, the ridge and eaves heights and the neighbours' daylight on the page — the relationships Sevenoaks District Council's officers weigh first — and submit a validation-complete pack, whether that is a lawful development certificate, a prior-approval notification or a full householder application.
Below is Sevenoaks District Council's real householder 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. A complete, policy-literate extension pack anticipates those pressure points before submission, which is why professionally drawn applications are decided faster and refused less often than DIY ones.
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.
Across Sevenoaks, Westerham and Kemsing, the extension that lands most often is the single-storey rear addition — a glazed kitchen-diner across the back of the house, kept within the permitted-development depth or taken to a full application where the ground floor wants more. On the borough's victorian and edwardian villas and terraces around sevenoaks town, a side-return infill frequently pairs with it to square off the plan; on wider larger country properties in the rural south, a two-storey side or rear extension can add a bedroom above without swallowing the garden.
Over half the district lies within the Kent Downs or High Weald National Landscapes (AONBs), where landscape protection shapes design and siting. We size the extension to the amenity and daylight tests, match the roof and materials to the host house, and keep enough garden to satisfy Sevenoaks District Council's space standards — so the scheme answers the borough's questions before an objection can raise them. Where permitted-development rights are used up or removed, we prepare the householder application to the council's extension design guidance instead.
We draw extensions on every street in the borough. A few of the neighbourhoods where Sevenoaks projects come up most often:
Extension drawings for Sevenoaks's the historic market-town core around the High Street and The Vine, with a Georgian and Victorian townscape — footprint-checked, daylight-tested and drawn to Sevenoaks District Council's guidance.
Extension drawings for Westerham's a historic market town with a conservation-area centre — footprint-checked, daylight-tested and drawn to Sevenoaks District Council's guidance.
Extension drawings for Kemsing's a downland village where front gardens and boundaries are controlled by an Article 4 direction — footprint-checked, daylight-tested and drawn to Sevenoaks District Council's guidance.
Extension drawings for Otford's a historic green-belt village of vernacular cottages around the pond — footprint-checked, daylight-tested and drawn to Sevenoaks District Council's guidance.
Extension drawings for Edenbridge's a small town on the district's southern High Weald edge — footprint-checked, daylight-tested and drawn to Sevenoaks District Council's guidance.
Extension drawings for Swanley's a denser, more suburban postwar settlement to the north — footprint-checked, daylight-tested and drawn to Sevenoaks District Council's guidance.
The right extension in Sevenoaks depends on your house type and how much garden you can give up. This is how the main options compare on planning route and what they add.
| Extension type | Permitted development? | What it adds | What Sevenoaks District Council checks |
|---|---|---|---|
| Single-storey rear | Often, within 3m/4m depth (6m/8m via prior approval) | Bigger kitchen-diner across the back | Depth, height, neighbour daylight (45°) |
| Side-return infill | Sometimes, if within width and height limits | Squares off an L-shaped ground floor | Width vs the original house, glazing to boundary |
| Two-storey rear/side | No — full application | Extra bedroom or bathroom above | Bulk, overlooking, 7m rear-boundary gap |
| Wraparound (rear + side) | No — full application | Whole-width open-plan ground floor | Combined footprint and garden retained |
Route depends on your street — conservation areas such as Sevenoaks High Street and The Vine and Article 4 directions can remove permitted-development rights.
A fixed process built around how Sevenoaks District Council validates and decides householder extension applications — most drawings are submission-ready within seven days of survey.
Tell us your Sevenoaks postcode and house type. We confirm your conservation and Article 4 status, how much permitted-development depth you have left, and score your odds against live Sevenoaks District Council decisions.
We measure the existing footprint, floor and eaves levels, boundary distances and the neighbours' window positions — the numbers the depth limits and daylight tests depend on.
Chartered designers develop the single-storey, two-storey or side extension to your brief, drawn inside the permitted-development limits or to Sevenoaks District Council's extension design guidance.
We submit the certificate, prior-approval notice or application, manage validation and case-officer queries, and revise the drawings free until Sevenoaks District Council issues its decision.
Not always. A single-storey rear extension up to 3 metres deep on a terrace or semi, or 4 metres on a detached house, and no higher than 4 metres, is usually permitted development. In Sevenoaks you will need to apply to Sevenoaks District Council for two-storey extensions, side extensions wider than half the house, anything forward of the front wall, deeper rear extensions under the larger-home prior-approval route, and any extension in a conservation area such as Sevenoaks High Street and The Vine.
Standard permitted development allows 3 metres on a terraced or semi-detached house and 4 metres on a detached one. The larger-home extension scheme can double that to 6 or 8 metres, but it needs a prior-approval notification to Sevenoaks District Council and a neighbour-consultation period, and it does not apply on designated land such as Sevenoaks's conservation areas. We confirm which route your property qualifies for before drawing.
Two-storey and double-storey extensions almost always need a full householder application to Sevenoaks District Council, because they fall outside permitted development on most homes. The council looks closely at bulk, overlooking of neighbours and the 7-metre gap a two-storey rear extension must keep from the rear boundary. We design to those tests and show the daylight and privacy angles on the drawings.
A householder planning application in Sevenoaks runs to a statutory eight-week target, a larger-home prior-approval notification to around six weeks including the neighbour-consultation period, and a lawful development certificate to eight weeks. Incomplete submissions stall at validation, so we submit a complete pack and manage officer queries to keep the decision on schedule. Sevenoaks District Council is the decision-maker.
Yes — planning permission and building regulations are separate consents, and almost every extension needs both. Planning governs whether you can build it; building control governs how it is built, covering structure, insulation, drainage and fire safety. We prepare the building-regulations drawings alongside the planning set so Sevenoaks District Council's building control or an approved inspector can sign the work off.
Every house and brief is different, so we price each Sevenoaks extension individually and send a fixed, no-obligation quote back within one working day. It covers the full drawing pack with free revisions until Sevenoaks District Council approves, and we tell you upfront whether your extension qualifies as permitted development. Call 020 7864 7245 to get started.
Answer five quick questions and get a free planning score for your exact address — instantly. Then, if you want the full picture, unlock the detailed analysis: your council's live approval rates, local precedents, constraints on your street and a step-by-step route to permission.
Same fixed quotes, same fast drawings — wherever your project is.