The fast route to a deep single-storey rear extension in Marlborough West — up to 6 metres on an attached house or 8 on a detached one — via Wiltshire Council's prior approval scheme rather than a full planning application.
Wiltshire Council granted 96% of the householder planning decisions it made in its latest published year — 9 points above the 87% England-wide householder average. Marlborough West contains AVEBURY, EAST KENNETT, LOCKERIDGE conservation areas (AVEBURY designated 1975), so materials, fenestration and roof form are assessed against the appraisal, which is where a policy-literate drawing pack earns its keep. Its dominant Victorian (1837–1901) and interwar (1918–1939) housing stock sets the design brief on most streets.
Class A and Class B set the thresholds — a rear dormer to 40m³ on a terrace or 50m³ on a semi or detached, and a single-storey rear extension to 3m on a terrace or 4m on a detached house — beyond which Wiltshire Council needs a full application. Marlborough West carries at least one Article 4 direction, and conservation areas including AVEBURY, EAST KENNETT and LOCKERIDGE remove those rights outright, so we confirm your exact address before a line is drawn. A validated householder application in Marlborough West is determined against an 8-week statutory target.
AVEBURY (conservation area designated in 1975), EAST KENNETT (conservation area designated in 1974), LOCKERIDGE (conservation area designated in 1985), MANTON (conservation area designated in 1985), MARLBOROUGH (conservation area designated in 1971), WEST KENNETT (conservation area designated in 1975), Avebury (civil parish within Marlborough West), Berwick Bassett (civil parish within Marlborough West), Marlborough (civil parish within Marlborough West), East Kennett (civil parish within Marlborough West), Fyfield (civil parish within Marlborough West) and West Overton (civil parish within Marlborough West) — these are the Marlborough West pockets our drawings cover most. Heritage designations here include AVEBURY, EAST KENNETT, LOCKERIDGE, MANTON, MARLBOROUGH and WEST KENNETT. Wiltshire Council weighs each proposal against Wiltshire Council's development plan and the design policies it applies to householder applications, where the 2,840 homes here are 24% pre-1900, 18% 1983-1992, 8% 1930-1939, which is what sets the realistic roof and rear-projection options. On roofs the borough is steeply pitched slate roofs, valley gutters and party parapets typical of pre-1900 building and trussed-rafter roofs typical of 1980s building, over Victorian and earlier houses (24% of 2,840 homes), 1980s estate houses (18%) and 1930s semi-detached and detached houses (8%).
Heritage designation is the single biggest variable in Marlborough West, and it is address-specific: AVEBURY (conservation area designated in 1975), EAST KENNETT (conservation area designated in 1974), LOCKERIDGE (conservation area designated in 1985), MANTON (conservation area designated in 1985), MARLBOROUGH (conservation area designated in 1971) and WEST KENNETT (conservation area designated in 1975). Inside those boundaries permitted development is curtailed and Wiltshire Council assesses materials, window detail and roof form against the area's own appraisal, so a scheme that would be waved through two streets away can need a full application here.
Beyond the designated areas, Marlborough West takes in Avebury, Berwick Bassett, Marlborough, East Kennett, Fyfield and West Overton. Wiltshire Council has 48 recorded Article 4 directions, removing permitted development for rear and side extensions and other roof alterations, including rooflights — check the address before assuming PD applies in Marlborough West.
On stock, Marlborough West is Victorian and earlier houses (24% of 2,840 homes), 1980s estate houses (18%) and 1930s semi-detached and detached houses (8%) — which is why steeply pitched slate roofs, valley gutters and party parapets typical of pre-1900 building and trussed-rafter roofs typical of 1980s building govern what a loft or rear projection can realistically be. Wiltshire Council decided 1,779 householder applications in the latest published year and granted 96%, with 53% issued inside the eight-week target. We work from the council's own published record.
The full build-period split for Marlborough West runs pre-1900 24% (680 homes), 1900-1918 6% (160 homes), 1919-1929 0% (10 homes), 1930-1939 8% (220 homes), 1945-1954 2% (50 homes), 1955-1964 5% (140 homes), 1965-1972 7% (200 homes), 1973-1982 5% (140 homes), 1983-1992 18% (510 homes), 1993-1999 4% (110 homes) and 2000-2008 6% (160 homes). That distribution is why pre-1900 detailing dominates the drawings here, and it is measured from council-tax records rather than assumed from the street name.
Wiltshire Council also decides for Aldbourne & Ramsbury, Amesbury West, Avon Valley, Box & Colerne, By Brook, Corsham Ladbrook, Corsham Pickwick and Corsham Without, so a decision in Marlborough West sits inside a wider pattern of decisions we track across the same authority — useful when an officer cites a precedent from the next area over.
The Article 4 directions recorded for this council include Ashley, Avebury, Baydon 1 and Baydon 2. Each removes a specific permitted-development right inside its own boundary, which is why the check is done on the address rather than on the town.
Published figures for Marlborough West and Wiltshire Council. These are the numbers that decide what is realistic on your street, so we work from them rather than from national averages.
| Measure | Marlborough West |
|---|---|
| Dwellings recorded | 2,840 |
| Built pre-1900 | 680 (24%) |
| Built 1900-1918 | 160 (6%) |
| Built 1919-1929 | 10 (0%) |
| Built 1930-1939 | 220 (8%) |
| Built 1945-1954 | 50 (2%) |
| Built 1955-1964 | 140 (5%) |
| Built 1965-1972 | 200 (7%) |
| Built 1973-1982 | 140 (5%) |
| Built 1983-1992 | 510 (18%) |
| Built 1993-1999 | 110 (4%) |
| Built 2000-2008 | 160 (6%) |
| Built before 1919 | 30% |
| Built 1919–1939 | 8% |
| Built 1945–2008 | 46% |
| Conservation areas in Marlborough West | 6 (AVEBURY, EAST KENNETT…) |
| Conservation areas district-wide | 245 |
| Article 4 directions recorded | 48 |
| Householder applications decided | 1,779 |
| Householder applications granted | 96% |
| Decided within 8 weeks | 53% |
Dwelling stock from VOA council-tax data at 31 March 2025; conservation-area and Article 4 counts from planning.data.gov.uk (MHCLG); decision figures are Wiltshire Council's own, from MHCLG live table PS2 for the year to 31 March 2026.
The ordinary Class A limits stop a single-storey rear extension at 3 metres on an attached house and 4 on a detached one. The larger home extension scheme doubles both, on condition that the council is told first. That notification is not an application for permission — the council cannot refuse on design, materials or policy grounds. It can only consider the effect on the amenity of adjoining premises, and only if a neighbour actually objects during the 21-day consultation.
The other conditions still apply and are strict: single storey only, no higher than 4 metres, eaves no higher than the existing eaves, and no more than half the land around the original house covered. It is not available on designated land, so a house in a conservation area such as AVEBURY and EAST KENNETT cannot use it at all. Materials must be similar to the existing house, and the extension must not include a veranda, balcony or raised platform.
Marlborough West is largely Victorian and earlier houses (24% of 2,840 homes), 1980s estate houses (18%) and 1930s semi-detached and detached houses (8%). Marlborough West contains AVEBURY, EAST KENNETT, LOCKERIDGE conservation areas (AVEBURY designated 1975), so materials, fenestration and roof form are assessed against the appraisal, which matters here because an objecting neighbour puts amenity squarely in front of a case officer. Wiltshire Council has 48 recorded Article 4 directions, removing permitted development for rear and side extensions and other roof alterations, including rooflights — check the address before assuming PD applies in Marlborough West.
The scheme is available where all of these hold. Fail any one and it is a full application to Wiltshire Council instead:
We prepare the notification pack Wiltshire Council needs — plans, elevations, a site plan with the adjoining owners identified — and manage the 21-day neighbour consultation so the 42-day clock is not restarted by an incomplete submission.
Below is Wiltshire Council's real householder decision record, drawn from official planning statistics and refreshed as new data lands. Wiltshire Council granted 96% of its householder applications in the year to 31 March 2026, and AVEBURY shapes what is approved here. Prior approval turns on neighbour amenity alone, so the drawings that matter are the ones showing the relationship to the boundary.
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 AVEBURY, EAST KENNETT and LOCKERIDGE, the notifications that clear without objection are the ones that treat the neighbour as the audience. We show the extension in section against the boundary, demonstrate the 45-degree daylight relationship to the nearest habitable window, and where the plot is tight we taper the depth away from the boundary rather than running the full 6 metres to the fence.
The 2,840 homes here are 24% pre-1900, 18% 1983-1992, 8% 1930-1939, which is what sets the realistic roof and rear-projection options. Where an objection does arrive, the council's assessment is narrow: loss of light, outlook and overbearing effect on the adjoining property, nothing else. A pack that has already answered those three points on the drawings usually survives an objection, whereas one that leaves them to the officer's imagination usually does not.
We prepare prior-approval notifications across Marlborough West. A few of the areas where deep rear extensions come up most often:
Prior approval drawings for AVEBURY — conservation area designated in 1975 — dimensioned to the 6m and 8m limits and prepared for Wiltshire Council's neighbour consultation.
Prior approval drawings for EAST KENNETT — conservation area designated in 1974 — dimensioned to the 6m and 8m limits and prepared for Wiltshire Council's neighbour consultation.
Prior approval drawings for LOCKERIDGE — conservation area designated in 1985 — dimensioned to the 6m and 8m limits and prepared for Wiltshire Council's neighbour consultation.
Prior approval drawings for MANTON — conservation area designated in 1985 — dimensioned to the 6m and 8m limits and prepared for Wiltshire Council's neighbour consultation.
Prior approval drawings for MARLBOROUGH — conservation area designated in 1971 — dimensioned to the 6m and 8m limits and prepared for Wiltshire Council's neighbour consultation.
Prior approval drawings for WEST KENNETT — conservation area designated in 1975 — dimensioned to the 6m and 8m limits and prepared for Wiltshire Council's neighbour consultation.
Same extension, two routes, very different tests.
| Route | Depth allowed | What the council may consider | Timescale |
|---|---|---|---|
| Ordinary Class A permitted development | 3m attached / 4m detached | Nothing — no application needed | Immediate |
| Larger home extension prior approval | 6m attached / 8m detached | Amenity of adjoining premises, only if a neighbour objects | 21-day consultation, 42-day determination |
| Full householder application | No fixed limit | Design, materials, policy, amenity, everything | 8-week target |
| Any of these on designated land | 3m / 4m only | Prior approval scheme unavailable | Full application beyond the limits |
Limits and procedure from the GPDO 2015, Schedule 2, Part 1, Class A and paragraph A.4, made permanent by amendment in 2019.
A process built around the 21-day consultation, which is where these schemes are won or lost.
Send us your Marlborough West postcode and house type. We confirm whether the property is on designated land, whether the scheme is available, and what depth you can realistically take.
We measure the original rear wall, eaves height, boundary distances and the neighbouring windows that the amenity assessment will turn on.
We draw the extension to the 6m or 8m limit with the boundary relationship shown in section, and prepare the written description and adjoining-owner details Wiltshire Council needs to start the consultation.
We submit, track the 21-day consultation and the 42-day determination, respond to any objection on amenity grounds, and revise free until the decision.
Three metres on a terraced or semi-detached house and four on a detached one under ordinary permitted development. Under the larger home extension prior approval scheme those double to six and eight metres, provided you notify Wiltshire Council before starting and the conditions on height, materials and land coverage are met. The scheme is not available on designated land. This applies to your Marlborough West address specifically.
It is a notification, not an application for permission. You tell Wiltshire Council what you intend to build, it writes to the adjoining owners, and they have 21 days to object. If nobody objects, you may build. If someone does, the council assesses the effect on the amenity of adjoining premises and must decide within 42 days. Design and policy are not in scope. This applies to your Marlborough West address specifically.
The council then considers the impact on the amenity of the adjoining property — loss of light, loss of outlook, and overbearing effect — and nothing else. It cannot refuse because it dislikes the design or the materials. We prepare the drawings so those three questions are already answered in section and on the site plan, which is what usually carries an objected scheme through. This applies to your Marlborough West address specifically. Wiltshire Council is the decision-maker.
No. The larger home extension scheme is unavailable on designated land, which includes conservation areas such as AVEBURY and EAST KENNETT, national landscapes, national parks and world heritage sites. On those properties the ordinary 3-metre and 4-metre limits apply, and anything deeper needs a full householder application to Wiltshire Council. This applies to your Marlborough West address specifically.
Twenty-one days for the neighbour consultation, and a maximum of 42 days from a valid submission for the council to determine it. If the council does not respond within 42 days you may proceed as notified. That deadline is the scheme's real advantage over a full application, and it is why validation completeness matters so much. This applies to your Marlborough West address specifically. Wiltshire Council is the decision-maker.
Yes — always. Prior approval deals only with the planning position. A 6-metre rear extension still needs building control approval for foundations, structure, drainage, thermal performance and fire safety, and the beam over the opening into the existing house needs designing and calculating. We prepare both sets so the notified scheme is the buildable one. This applies to your Marlborough West address specifically. Wiltshire Council is the decision-maker.
We quote each Marlborough West scheme individually, because plot shape and the boundary relationship drive the work, and send a fixed, no-obligation quote within one working day. It covers the notification pack and free revisions until Wiltshire Council determines it. Call 020 7864 7245 to start.
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