
Back-of-house extension drawings for Long Ashton homes — the glazed kitchen-diner across the rear, drawn to North Somerset Council's depth and daylight limits, delivered in days and revised free until your decision, with a free approval-odds check first.
North Somerset Council granted 93% of the householder planning decisions it made in its latest published year — 6 points above the 87% England-wide householder average. Long Ashton contains Leighwoods, Long Ashton, Long Ashton Westleaze & Wyke and Yanley conservation areas (Leighwoods designated 1977), 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 postwar (1945–1970) 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 North Somerset Council needs a full application. Long Ashton carries at least one Article 4 direction, and conservation areas including Leighwoods, Long Ashton and Long Ashton Westleaze & Wyke and Yanley remove those rights outright, so we confirm your exact address before a line is drawn. A validated householder application in Long Ashton is determined against an 8-week statutory target.
Leighwoods (conservation area designated in 1977), Long Ashton (conservation area designated in 1980), Long Ashton Westleaze & Wyke and Yanley (conservation area designated in 1988) and Wraxall and Failand (civil parish within Long Ashton) — these are the Long Ashton pockets our drawings cover most. Heritage designations here include Leighwoods, Long Ashton and Long Ashton Westleaze & Wyke and Yanley. North Somerset Council weighs each proposal against North Somerset Council's adopted local plan and its householder design guidance, where the 3,530 homes here are 18% 1955-1964, 16% 2000-2008, 11% pre-1900, 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 trussed-rafter roofs typical of 2000s building, over late-1950s and early-1960s houses (18% of 3,530 homes), 2000s houses and apartments (16%) and Victorian and earlier houses (11%).
Heritage designation is the single biggest variable in Long Ashton, and it is address-specific: Leighwoods (conservation area designated in 1977), Long Ashton (conservation area designated in 1980) and Long Ashton Westleaze & Wyke and Yanley (conservation area designated in 1988). Inside those boundaries permitted development is curtailed and North Somerset 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, Long Ashton takes in Wraxall and Failand. North Somerset Council has 38 recorded Article 4 directions — check the address before assuming PD applies in Long Ashton.
On stock, Long Ashton is late-1950s and early-1960s houses (18% of 3,530 homes), 2000s houses and apartments (16%) and Victorian and earlier houses (11%) — which is why shallow gabled roofs typical of that period's building and trussed-rafter roofs typical of 2000s building govern what a loft or rear projection can realistically be. North Somerset Council decided 620 householder applications in the latest published year and granted 93%, with 73% issued inside the eight-week target. We work from the council's own published record.
The full build-period split for Long Ashton runs pre-1900 11% (400 homes), 1900-1918 2% (80 homes), 1919-1929 6% (220 homes), 1930-1939 6% (200 homes), 1945-1954 6% (210 homes), 1955-1964 18% (630 homes), 1965-1972 7% (240 homes), 1973-1982 8% (280 homes), 1983-1992 5% (160 homes), 1993-1999 8% (280 homes) and 2000-2008 16% (580 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.
North Somerset Council also decides for Backwell, Banwell & Winscombe, Blagdon & Churchill, Clevedon East, Congresbury & Puxton, Gordano Valley, Hutton & Locking and Nailsea West End, so a decision in Long Ashton 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 11-15 Mayfair Avenue, Nailsea (1), Agricultural land at Weston-in-Gordano, Banwell Conservation Area (1) and Battery Lane, Portishead (1). 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 Long Ashton and North Somerset Council. These are the numbers that decide what is realistic on your street, so we work from them rather than from national averages.
| Measure | Long Ashton |
|---|---|
| Dwellings recorded | 3,530 |
| Built pre-1900 | 400 (11%) |
| Built 1900-1918 | 80 (2%) |
| Built 1919-1929 | 220 (6%) |
| Built 1930-1939 | 200 (6%) |
| Built 1945-1954 | 210 (6%) |
| Built 1955-1964 | 630 (18%) |
| Built 1965-1972 | 240 (7%) |
| Built 1973-1982 | 280 (8%) |
| Built 1983-1992 | 160 (5%) |
| Built 1993-1999 | 280 (8%) |
| Built 2000-2008 | 580 (16%) |
| Built before 1919 | 14% |
| Built 1919–1939 | 12% |
| Built 1945–2008 | 67% |
| Conservation areas in Long Ashton | 3 (Leighwoods, Long Ashton…) |
| Conservation areas district-wide | 39 |
| Article 4 directions recorded | 38 |
| Householder applications decided | 620 |
| Householder applications granted | 93% |
| Decided within 8 weeks | 73% |
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 North Somerset Council's own, from MHCLG live table PS2 for the year to 31 March 2026.
The rear extension is the workhorse of Long Ashton home improvement — it is how a dark back kitchen becomes an open family room facing the garden. Because the borough is built largely from late-1950s and early-1960s houses (18% of 3,530 homes), 2000s houses and apartments (16%) and Victorian and earlier houses (11%), most back walls sit close to a neighbour on at least one side, and that proximity, not the design, is what North Somerset Council scrutinises. The council reads the proposal against North Somerset Council's adopted local plan and its householder design guidance, and the first line an officer draws is the 45-degree splay from the neighbour's nearest window.
So the drawings live or die on geometry. We set the depth against the exact permitted-development figure, hold the eaves and the flat-roof or lantern build-up under the 4-metre height ceiling, and show the projection tested against both the 45-degree plan angle and the 25-degree section angle to the neighbouring windows. Long Ashton contains Leighwoods, Long Ashton, Long Ashton Westleaze & Wyke and Yanley conservation areas (Leighwoods designated 1977), so materials, fenestration and roof form are assessed against the appraisal, so the rear elevation is composed around it rather than corrected after an objection.
Where the property sits in a conservation area — Leighwoods, Long Ashton and Long Ashton Westleaze & Wyke and Yanley among Long Ashton's — the larger-home extension route is switched off and even a modest rear addition needs consent. North Somerset Council has 38 recorded Article 4 directions — check the address before assuming PD applies in Long Ashton. We confirm the designation before the survey.

Many single-storey rear extensions in Long Ashton are permitted development and need no application. You will normally need to apply to North Somerset Council, or use the larger-home prior-approval route, if any of these apply:
We draw the depth, the roof build-up and the daylight splays to each neighbour on the page — the tests North Somerset Council's officers apply first — and submit a validation-complete pack, whether that is a lawful development certificate, a larger-home prior-approval notice or a full householder application.
Below is North Somerset Council's real householder decision record, taken from official planning statistics and refreshed as new data lands. North Somerset Council granted 93% of its householder applications in the year to 31 March 2026, and Leighwoods shapes what is approved here. Rear extensions turn most often on neighbour daylight and depth, so a drawing pack that proves those tests upfront is decided faster and refused less often than a DIY submission.
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 Leighwoods, Long Ashton and Long Ashton Westleaze & Wyke and Yanley, the approved rear extension is typically a single-storey glazed box within the depth limit, roofed either flat with a lantern or in a shallow mono-pitch, and finished in brick or render to match the host wall. On the borough's late-1950s and early-1960s houses (18% of 3,530 homes), keeping the projection to the permitted-development figure often avoids an application entirely; where owners want the full 6 metres, the larger-home route succeeds when the neighbour-consultation period passes without a sustained objection.
The 3,530 homes here are 18% 1955-1964, 16% 2000-2008, 11% pre-1900, which is what sets the realistic roof and rear-projection options. We keep the extension inside the daylight splays, set any glazed roof below the first-floor cill, and retain the garden depth North Somerset Council expects — so the back elevation answers the amenity case before a neighbour can lodge one. Two-storey rear extensions we draw with the 7-metre boundary gap and privacy screening resolved on the plan.

We draw rear extensions on every street in the borough. A few of the neighbourhoods where Long Ashton back-of-house projects come up most often:
Rear extension drawings for Leighwoods's conservation area designated in 1977 — depth-checked, daylight-tested and drawn to North Somerset Council's guidance.
Rear extension drawings for Long Ashton's conservation area designated in 1980 — depth-checked, daylight-tested and drawn to North Somerset Council's guidance.
Rear extension drawings for Long Ashton Westleaze & Wyke and Yanley's conservation area designated in 1988 — depth-checked, daylight-tested and drawn to North Somerset Council's guidance.
Rear extension drawings for Wraxall and Failand's civil parish within Long Ashton — depth-checked, daylight-tested and drawn to North Somerset Council's guidance.
How far you can extend at the back in Long Ashton depends on your house type and the route you take. This is how the options compare.
| Route | Depth allowed | Consent needed | What North Somerset Council checks |
|---|---|---|---|
| Standard permitted development | 3m terrace/semi · 4m detached | Lawful development certificate (optional) | Depth, 4m height, materials |
| Larger-home prior approval | 6m terrace/semi · 8m detached | Prior-approval notice + neighbour consultation | Neighbour objections on amenity |
| Full householder application | Beyond the above, or two-storey | Full planning permission | Daylight (45°/25°), bulk, garden retained |
| Conservation area | Case by case | Full planning permission | Character, roof form, boundary treatment |
The larger-home route is switched off on designated land — conservation areas such as Leighwoods and Long Ashton and Article 4 streets need a full application.
A fixed process built around how North Somerset Council validates and decides rear-extension applications — most drawings are submission-ready within seven days of survey.
Send us your Long Ashton postcode and house type. We confirm your conservation and Article 4 status, how much rear-extension depth you have under permitted development, and score your odds against live North Somerset Council decisions.
We measure the original rear wall, floor and eaves levels, side and rear boundary distances and the neighbours' window positions — the numbers the depth limit and daylight splays depend on.
Chartered designers develop the single or two-storey rear extension to your brief, drawn inside the permitted-development limits or to North Somerset Council's extension design guidance, with the daylight angles shown.
We submit the certificate, prior-approval notice or application, handle validation and case-officer queries, and revise the drawings free until North Somerset Council issues its decision.
Often not. 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 Long Ashton. You will need to involve North Somerset Council for anything deeper via the larger-home route, for two-storey rear extensions, and for any rear extension in a conservation area such as Leighwoods and Long Ashton, where those permitted-development rights fall away.
The larger-home extension scheme lets a single-storey rear extension reach 6 metres on a terrace or semi, or 8 metres on a detached house — double the standard allowance. It is not automatic: you submit a prior-approval notification to North Somerset Council, neighbours are consulted, and if one objects on amenity grounds the council rules on it. It also does not apply on designated land such as Long Ashton's conservation areas.
It is the daylight test North Somerset Council applies to protect neighbours. Drawn on plan, a line at 45 degrees from the midpoint of the neighbour's nearest ground-floor window should not be crossed by your extension; a companion 25-degree line is checked in section. If the projection breaches it, the extension is likely to be shortened or refused, so we test and prove it on the drawings before submission. This applies to your Long Ashton address specifically.
A two-storey rear extension almost always needs a full householder application to North Somerset Council, as it sits outside permitted development on most homes. The council checks that it stays at least 7 metres from the rear boundary, does not overbear the neighbours and avoids new overlooking. We resolve the boundary gap, privacy and daylight on the plans so the application is decided on its merits. This applies to your Long Ashton address specifically.
Frequently, yes. If the rear extension involves work to a shared wall, building up to the boundary, or excavating foundations near a neighbour's structure, the Party Wall etc. Act applies and you must serve notice — this is separate from North Somerset Council's planning decision. We flag it early and can prepare the drawings a party-wall surveyor needs alongside the planning set. This applies to your Long Ashton address specifically.
We price each Long Ashton rear extension on its own footprint and send a fixed, no-obligation quote within one working day. It covers the full drawing pack with free revisions until North Somerset Council approves, and we confirm at the outset whether your extension is permitted development, needs prior approval, or a full application. Call 020 7864 7245 to begin.
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Same fixed quotes, same fast drawings — wherever your project is.