Two-storey extension drawings for Kensington and Chelsea homes — bedroom above, living space below, drawn against the 3-metre projection and 7-metre boundary rules and to the Royal Borough of Kensington and Chelsea's design guidance, delivered in days and revised free until your decision.
the Royal Borough of Kensington and Chelsea granted 85% of the householder planning decisions it made in its latest published year — 2 points below the 87% England-wide householder average. The borough runs the strictest basement policy in London — broadly one storey deep, under no more than half the garden, with a construction traffic management plan, which is where a policy-literate drawing pack earns its keep. Its dominant Georgian (1714–1837) and Victorian (1837–1901) housing stock sets the design brief on most streets.
Under Class B, a rear dormer stays permitted development up to 40m³ of added roof volume on a terrace or 50m³ on a semi-detached or detached house, while Class A allows a single-storey rear extension of 3m beyond the original rear wall on a terrace and 4m on a detached house before a full application is needed. Kensington and Chelsea carries at least one Article 4 direction, and conservation areas including Chelsea, Kensington and Holland Park remove those rights outright, so we confirm your exact address before a line is drawn. A validated householder application in Kensington and Chelsea is determined against an 8-week statutory target.
Chelsea (stucco terraces and mews streets off the King's Road), Kensington (grand stucco terraces and mansion blocks), Notting Hill (the Ladbroke Estate's stucco terraces around communal garden squares), Holland Park (large detached villas and substantial mansion flats), Knightsbridge (red-brick mansion blocks and stucco terraces) and Earls Court (tall Victorian terraces widely subdivided into flats) — these are the Kensington and Chelsea pockets our drawings cover most. Heritage designations here include Chelsea, Kensington, Holland Park, Ladbroke and Brompton. the Royal Borough of Kensington and Chelsea weighs each proposal against the RBKC Consolidated Local Plan and the Basements SPD, where with the roofscape closely protected, mansard and roof additions are judged against the prevailing profile of each terrace group. Subdivided period houses are common around Earls Court and Notting Hill, and converted flats hold no householder permitted-development rights.. On roofs the borough is concealed butterfly roofs behind the terrace parapets and mansard roofs added to the stucco terraces, over stucco-fronted Georgian and Victorian terraces, purpose-built mansion blocks and mews houses behind the main streets.
Adding at first floor changes the question the case officer asks. A single-storey extension is judged mostly on daylight and garden loss; a two-storey extension is judged on overlooking, bulk against the neighbouring roofline, and whether it reads as part of the house or bolted onto it. Kensington and Chelsea is largely stucco-fronted Georgian and Victorian terraces, purpose-built mansion blocks and mews houses behind the main streets, and concealed butterfly roofs behind the terrace parapets and mansard roofs added to the stucco terraces set what a matching roof actually means here.
The permitted-development route exists but is narrow: 3 metres of rear projection, a 7-metre stand-off from the rear boundary, eaves and ridge no higher than the original, and side-facing upper windows obscure-glazed and non-opening below 1.7 metres above floor level. Most two-storey schemes fail one of those, usually the 7-metre boundary rule on a shorter garden, and go in as a full application instead. We establish which route applies before designing, because it changes the drawing set.
The borough runs the strictest basement policy in London — broadly one storey deep, under no more than half the garden, with a construction traffic management plan. Almost the entire borough falls within a conservation area, and Article 4 directions strip out permitted-development rights so even minor external changes on the Ladbroke or Chelsea streets need consent.
Some two-storey rear extensions are permitted development. You will need a full application to the Royal Borough of Kensington and Chelsea if any of these apply:
We set the projection and boundary distance on the site plan, prove the roof-pitch match on the elevations, and specify obscure glazing on the side windows — the three things the Royal Borough of Kensington and Chelsea checks first — then submit a validation-complete pack.
Below is the Royal Borough of Kensington and Chelsea's real householder decision record, drawn from official planning statistics and refreshed as new data lands. The Royal Borough grants a fair share of householder applications but under exacting design control, with borough-wide conservation status and its restrictive basement policy the defining constraints. Two-storey schemes attract more neighbour comment than any other householder work, so the overlooking and daylight case has to be made on the drawings.
Source: MHCLG planning application statistics (householder decisions, rolling year). 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 Chelsea, Kensington and Notting Hill, the schemes that succeed set the first floor back from the ground floor, keep the ridge below the original, and treat the flank wall as blank or obscure-glazed. On stucco-fronted georgian and victorian terraces, matching the eaves line matters more than matching the brick: an extension that carries the existing eaves through reads as original even in a different material.
With the roofscape closely protected, mansard and roof additions are judged against the prevailing profile of each terrace group. We draw the 45-degree daylight test from the neighbour's nearest habitable window, show the window positions in section, and set out the steel and foundation implications early — a two-storey extension changes the load path, so the structural design and the planning design have to be developed together rather than in sequence.
We draw two-storey extensions across Kensington and Chelsea. A few of the areas where they come up most often:
Two storey extension drawings for Chelsea — stucco terraces and mews streets off the King's Road — dimensioned against the 3m and 7m limits and drawn to the Royal Borough of Kensington and Chelsea's guidance.
Two storey extension drawings for Kensington — grand stucco terraces and mansion blocks — dimensioned against the 3m and 7m limits and drawn to the Royal Borough of Kensington and Chelsea's guidance.
Two storey extension drawings for Notting Hill — the Ladbroke Estate's stucco terraces around communal garden squares — dimensioned against the 3m and 7m limits and drawn to the Royal Borough of Kensington and Chelsea's guidance.
Two storey extension drawings for Holland Park — large detached villas and substantial mansion flats — dimensioned against the 3m and 7m limits and drawn to the Royal Borough of Kensington and Chelsea's guidance.
Two storey extension drawings for Knightsbridge — red-brick mansion blocks and stucco terraces — dimensioned against the 3m and 7m limits and drawn to the Royal Borough of Kensington and Chelsea's guidance.
Two storey extension drawings for Earls Court — tall Victorian terraces widely subdivided into flats — dimensioned against the 3m and 7m limits and drawn to the Royal Borough of Kensington and Chelsea's guidance.
The first-floor limits are tighter than the ground-floor ones. This is how the common cases compare.
| Scheme | Permitted development? | Deciding limit | What the Royal Borough of Kensington and Chelsea checks |
|---|---|---|---|
| Two-storey rear, 3m projection, 7m+ to boundary | Often yes | 3m projection / 7m boundary | Roof match, side-window glazing |
| Two-storey rear, under 7m to boundary | No — full application | Rear-boundary distance | Overlooking, daylight, garden loss |
| Two-storey side extension | No — full application | Side elevation | Gap to boundary, street rhythm |
| Two-storey wraparound | No — full application | Combined footprint | Bulk, massing, neighbour amenity |
| Any two-storey on designated land | No — full application | Designation | Character and appearance |
Limits from the GPDO 2015, Schedule 2, Part 1, Class A — two-storey rear extension conditions.
A fixed process built around how the Royal Borough of Kensington and Chelsea validates and decides two-storey applications.
Send us your Kensington and Chelsea postcode and garden depth. We measure the 7-metre boundary rule against your plot, confirm designation status, and score your odds against live the Royal Borough of Kensington and Chelsea decisions.
We measure the original rear wall, eaves and ridge heights, garden depth and every neighbouring window that faces the site — the inputs the daylight and overlooking case is built from.
Chartered designers develop the two-storey addition to your brief with the roof and eaves resolved, and we coordinate the load path so the structural scheme and the planning scheme are the same building.
We submit the application, manage validation and case-officer queries, and revise the drawings free until the Royal Borough of Kensington and Chelsea issues its decision.
Often, but not always. A two-storey rear extension can be permitted development if it projects no more than 3 metres, sits at least 7 metres from the rear boundary, does not exceed the existing eaves and ridge, and has obscure-glazed non-opening side windows below 1.7 metres. In Kensington and Chelsea, the 7-metre rule is what most commonly forces a full application to the Royal Borough of Kensington and Chelsea.
No part of a permitted-development two-storey rear extension may come within 7 metres of the boundary opposite the rear wall of the house. It exists to protect the neighbour behind you from being overlooked at first floor. On shorter Kensington and Chelsea gardens this is decisive, and we measure it on survey before any design work rather than discovering it at validation. the Royal Borough of Kensington and Chelsea is the decision-maker.
Not under permitted development — two-storey side extensions always need a full application to the Royal Borough of Kensington and Chelsea. They are assessed on the gap to the boundary, whether the street's rhythm of spaces between houses survives, and whether the extension is subordinate to the original. Setting the first floor back from the front building line and down from the ridge is what usually makes the difference.
Overlooking is the most common objection, and it is answerable on the drawings. We position habitable-room windows away from neighbouring gardens, obscure-glaze and fix shut anything on the flank below 1.7 metres, and show the sight lines in section. Where the geometry is tight, a rooflight or a high-level window gives the same daylight without the mutual overlooking that draws objections. This applies to your Kensington and Chelsea address specifically. the Royal Borough of Kensington and Chelsea is the decision-maker.
Almost certainly. Excavating within 3 metres of a neighbouring structure and building on or up to the boundary both trigger the Party Wall etc. Act 1996, and a two-storey extension usually does both. It is entirely separate from the Royal Borough of Kensington and Chelsea's planning decision, so we flag the notice period early and detail the junction on the drawings.
Yes. Adding a floor changes the load path from roof to foundation, so beams, padstones and foundation depths all need designing and calculating for building control. Planning and building regulations are separate consents, and the structural set is what building control assesses — we prepare both so the approved scheme is the buildable one. This applies to your Kensington and Chelsea address specifically. the Royal Borough of Kensington and Chelsea is the decision-maker.
We quote each Kensington and Chelsea two-storey extension individually, because plot depth, roof form and structural complexity vary house to house, and send a fixed, no-obligation quote within one working day. It covers the drawing pack with free revisions until the Royal Borough of Kensington and Chelsea approves. Call 020 7864 7245 to start.
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.