The fast route to a deep single-storey rear extension in Bolton & Slyne — up to 6 metres on an attached house or 8 on a detached one — via Lancaster City Council's prior approval scheme rather than a full planning application.
Lancaster City Council granted 87% of the householder planning decisions it made in its latest published year — level with the 87% England-wide householder average. Bolton & Slyne contains Bolton-le-Sands, Slyne conservation areas (Bolton-le-Sands designated 1981), so materials, fenestration and roof form are assessed against the appraisal, which is where a policy-literate drawing pack earns its keep. Its dominant interwar (1918–1939) and postwar (1945–1970) 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. In conservation areas such as Bolton-le-Sands and Slyne those rights are removed, so we confirm your exact address before a line is drawn. A validated householder application in Bolton & Slyne is determined against an 8-week statutory target.
Bolton-le-Sands (conservation area designated in 1981), Slyne (conservation area designated in 1981), Bolton-le-Sands (civil parish within Bolton & Slyne) and Slyne-with-Hest (civil parish within Bolton & Slyne) — these are the Bolton & Slyne pockets our drawings cover most. Heritage designations here include Bolton-le-Sands and Slyne. Lancaster City Council weighs each proposal against the adopted Lancaster local plan and Lancaster City Council's design guidance for householder work, where the 3,440 homes here are 28% 1955-1964, 13% 1930-1939, 12% 1965-1972, which is what sets the realistic roof and rear-projection options. On roofs the borough is shallow gabled roofs typical of that period's building and hipped roofs with shallow pitches typical of 1930s building, over late-1950s and early-1960s houses (28% of 3,440 homes), 1930s semi-detached and detached houses (13%) and late-1960s and early-1970s houses (12%).
Bolton & Slyne's designated heritage is specific, and it is the first thing we check against your address: Bolton-le-Sands (conservation area designated in 1981) and Slyne (conservation area designated in 1981). Inside those boundaries permitted development is curtailed and Lancaster City 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, Bolton & Slyne takes in Bolton-le-Sands and Slyne-with-Hest. No Article 4 direction is recorded for Lancaster City Council, but Bolton & Slyne's 2 conservation areas still limit permitted development on those streets.
On stock, Bolton & Slyne is late-1950s and early-1960s houses (28% of 3,440 homes), 1930s semi-detached and detached houses (13%) and late-1960s and early-1970s houses (12%) — which is why shallow gabled roofs typical of that period's building and hipped roofs with shallow pitches typical of 1930s building govern what a loft or rear projection can realistically be. Lancaster City Council decided 303 householder applications in the latest published year and granted 87%, with 74% issued inside the eight-week target. Those are the numbers our drawings are prepared against.
The full build-period split for Bolton & Slyne runs pre-1900 8% (290 homes), 1900-1918 2% (80 homes), 1919-1929 4% (150 homes), 1930-1939 13% (460 homes), 1945-1954 12% (410 homes), 1955-1964 28% (970 homes), 1965-1972 12% (420 homes), 1973-1982 6% (220 homes), 1983-1992 3% (110 homes), 1993-1999 3% (100 homes) and 2000-2008 2% (70 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.
Lancaster City Council also decides for Carnforth & Millhead, Castle, Ellel, Lower Lune Valley, Marsh, Overton, Scotforth West and Upper Lune Valley, so a decision in Bolton & Slyne 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.
Published figures for Bolton & Slyne and Lancaster City Council. These are the numbers that decide what is realistic on your street, so we work from them rather than from national averages.
| Measure | Bolton & Slyne |
|---|---|
| Dwellings recorded | 3,440 |
| Built pre-1900 | 290 (8%) |
| Built 1900-1918 | 80 (2%) |
| Built 1919-1929 | 150 (4%) |
| Built 1930-1939 | 460 (13%) |
| Built 1945-1954 | 410 (12%) |
| Built 1955-1964 | 970 (28%) |
| Built 1965-1972 | 420 (12%) |
| Built 1973-1982 | 220 (6%) |
| Built 1983-1992 | 110 (3%) |
| Built 1993-1999 | 100 (3%) |
| Built 2000-2008 | 70 (2%) |
| Built before 1919 | 11% |
| Built 1919–1939 | 18% |
| Built 1945–2008 | 67% |
| Conservation areas in Bolton & Slyne | 2 (Bolton-le-Sands, Slyne) |
| Conservation areas district-wide | 35 |
| Article 4 directions recorded | 0 |
| Householder applications decided | 303 |
| Householder applications granted | 87% |
| Decided within 8 weeks | 74% |
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 Lancaster City 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 Bolton-le-Sands and Slyne 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.
Bolton & Slyne is largely late-1950s and early-1960s houses (28% of 3,440 homes), 1930s semi-detached and detached houses (13%) and late-1960s and early-1970s houses (12%). Bolton & Slyne contains Bolton-le-Sands, Slyne conservation areas (Bolton-le-Sands designated 1981), 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. No Article 4 direction is recorded for Lancaster City Council, but Bolton & Slyne's 2 conservation areas still limit permitted development on those streets.
The scheme is available where all of these hold. Fail any one and it is a full application to Lancaster City Council instead:
We prepare the notification pack Lancaster City 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 Lancaster City Council's real householder decision record, drawn from official planning statistics and refreshed as new data lands. Lancaster City Council granted 87% of its householder applications in the year to 31 March 2026, and Bolton-le-Sands 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 Bolton-le-Sands, Slyne and Bolton-le-Sands, 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 3,440 homes here are 28% 1955-1964, 13% 1930-1939, 12% 1965-1972, 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 Bolton & Slyne. A few of the areas where deep rear extensions come up most often:
Prior approval drawings for Bolton-le-Sands — conservation area designated in 1981 — dimensioned to the 6m and 8m limits and prepared for Lancaster City Council's neighbour consultation.
Prior approval drawings for Slyne — conservation area designated in 1981 — dimensioned to the 6m and 8m limits and prepared for Lancaster City Council's neighbour consultation.
Prior approval drawings for Bolton-le-Sands — civil parish within Bolton & Slyne — dimensioned to the 6m and 8m limits and prepared for Lancaster City Council's neighbour consultation.
Prior approval drawings for Slyne-with-Hest — civil parish within Bolton & Slyne — dimensioned to the 6m and 8m limits and prepared for Lancaster City 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 Bolton & Slyne 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 Lancaster City 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 Lancaster City 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 Bolton & Slyne address specifically.
It is a notification, not an application for permission. You tell Lancaster City 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 Bolton & Slyne 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 Bolton & Slyne address specifically. Lancaster City Council is the decision-maker.
No. The larger home extension scheme is unavailable on designated land, which includes conservation areas such as Bolton-le-Sands and Slyne, 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 Lancaster City Council. This applies to your Bolton & Slyne 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 Bolton & Slyne address specifically. Lancaster City 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 Bolton & Slyne address specifically. Lancaster City Council is the decision-maker.
We quote each Bolton & Slyne 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 Lancaster City Council determines it. Call 020 7864 7245 to start.
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Same fixed quotes, same fast drawings — wherever your project is.