Annexe and granny-flat drawings for Downham Old Town homes — designed to stay ancillary to the main house rather than become a separate dwelling, drawn to Borough Council of King's Lynn and West Norfolk's policies, delivered in days and revised free until your decision.
Borough Council of King's Lynn and West Norfolk granted 95% of the householder planning decisions it made in its latest published year — 8 points above the 87% England-wide householder average. Downham Old Town contains the DOWNHAM MARKET CONSERVATION AREA conservation area (DOWNHAM MARKET CONSERVATION AREA 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 Edwardian (1901–1910) 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. Downham Old Town carries at least one Article 4 direction, and conservation areas including DOWNHAM MARKET CONSERVATION AREA remove those rights outright, so we confirm your exact address before a line is drawn. A validated householder application in Downham Old Town is determined against an 8-week statutory target.
DOWNHAM MARKET (conservation area designated in 1975) and Downham Market (civil parish within Downham Old Town) — these are the Downham Old Town pockets our drawings cover most. Heritage designations here include DOWNHAM MARKET CONSERVATION AREA. Borough Council of King's Lynn and West Norfolk weighs each proposal against the adopted Borough Council of King's Lynn and West Norfolk local plan and Borough Council of King's Lynn and West Norfolk's design guidance for householder work, where the 1,550 homes here are 14% 2000-2008, 13% 1900-1918, 12% pre-1900, which is what sets the realistic roof and rear-projection options. On roofs the borough is trussed-rafter roofs typical of 2000s building and pitched and hipped roofs with generous eaves typical of Edwardian building, over 2000s houses and apartments (14% of 1,550 homes), Edwardian houses (13%) and Victorian and earlier houses (12%).
What is permitted in Downham Old Town turns on designation first, so that is where we start: DOWNHAM MARKET (conservation area designated in 1975). Inside those boundaries permitted development is curtailed and Borough Council of King's Lynn and West Norfolk 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, Downham Old Town takes in Downham Market. Borough Council of King's Lynn and West Norfolk has 12 recorded Article 4 directions — check the address before assuming PD applies in Downham Old Town.
On stock, Downham Old Town is 2000s houses and apartments (14% of 1,550 homes), Edwardian houses (13%) and Victorian and earlier houses (12%) — which is why trussed-rafter roofs typical of 2000s building and pitched and hipped roofs with generous eaves typical of Edwardian building govern what a loft or rear projection can realistically be. Borough Council of King's Lynn and West Norfolk decided 521 householder applications in the latest published year and granted 95%, with 87% issued inside the eight-week target. We draw to that record rather than to a national average.
The full build-period split for Downham Old Town runs pre-1900 12% (180 homes), 1900-1918 13% (200 homes), 1919-1929 3% (50 homes), 1930-1939 3% (50 homes), 1945-1954 4% (60 homes), 1955-1964 8% (130 homes), 1965-1972 6% (90 homes), 1973-1982 6% (100 homes), 1983-1992 5% (70 homes), 1993-1999 5% (70 homes) and 2000-2008 14% (220 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.
Borough Council of King's Lynn and West Norfolk also decides for Airfield, Bircham with Rudhams, Brancaster, Dersingham, Feltwell, Heacham, Methwold and Terrington, so a decision in Downham Old Town 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 Coastal area Heacham, Coastal area Snettisham, Holme next the Sea and Kings Lynn Conservation Area. 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 Downham Old Town and Borough Council of King's Lynn and West Norfolk. These are the numbers that decide what is realistic on your street, so we work from them rather than from national averages.
| Measure | Downham Old Town |
|---|---|
| Dwellings recorded | 1,550 |
| Built pre-1900 | 180 (12%) |
| Built 1900-1918 | 200 (13%) |
| Built 1919-1929 | 50 (3%) |
| Built 1930-1939 | 50 (3%) |
| Built 1945-1954 | 60 (4%) |
| Built 1955-1964 | 130 (8%) |
| Built 1965-1972 | 90 (6%) |
| Built 1973-1982 | 100 (6%) |
| Built 1983-1992 | 70 (5%) |
| Built 1993-1999 | 70 (5%) |
| Built 2000-2008 | 220 (14%) |
| Built before 1919 | 25% |
| Built 1919–1939 | 6% |
| Built 1945–2008 | 48% |
| Conservation areas in Downham Old Town | 1 (DOWNHAM MARKET CONSERVATION AREA) |
| Conservation areas district-wide | 44 |
| Article 4 directions recorded | 12 |
| Householder applications decided | 521 |
| Householder applications granted | 95% |
| Decided within 8 weeks | 87% |
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 Borough Council of King's Lynn and West Norfolk's own, from MHCLG live table PS2 for the year to 31 March 2026.
Councils do not decide annexes on square metres. They decide whether, once built, the accommodation forms part of one planning unit with the main house or a second one beside it. Borough Council of King's Lynn and West Norfolk looks at whether the garden is shared or divided, whether the annexe has its own street access and address, whether the occupier could live there entirely independently, and whether the two households would function as one. That is the whole case, and it is made or lost on the layout.
Downham Old Town is largely 2000s houses and apartments (14% of 1,550 homes), Edwardian houses (13%) and Victorian and earlier houses (12%), which shapes the realistic options: converting part of the existing house, extending it, or building a detached unit in the garden. A detached annexe can sometimes sit under Class E as an outbuilding incidental to the enjoyment of the dwellinghouse — but sleeping accommodation is generally not "incidental", so a garden annexe with a bedroom usually needs its own permission rather than relying on outbuilding rights.
In Downham Old Town's conservation areas — including DOWNHAM MARKET CONSERVATION AREA — a garden building is also judged on its effect on the character of the area, which limits height and footprint before the use question is reached. Borough Council of King's Lynn and West Norfolk has 12 recorded Article 4 directions — check the address before assuming PD applies in Downham Old Town.
An annexe almost always needs an application to Borough Council of King's Lynn and West Norfolk. Expect one where any of these apply:
We plan the annexe so its relationship to the main house is visible on the page — shared garden, connected access, a layout that reads as one household — and set out the case Borough Council of King's Lynn and West Norfolk has to test, rather than leaving the officer to assume the worst.
Below is Borough Council of King's Lynn and West Norfolk's real householder decision record, drawn from official planning statistics and refreshed as new data lands. Borough Council of King's Lynn and West Norfolk granted 95% of its householder applications in the year to 31 March 2026, and DOWNHAM MARKET CONSERVATION AREA shapes what is approved here. Annexe applications are decided on use as much as design, so the supporting case matters as much as the elevations.
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 DOWNHAM MARKET and Downham Market, the annexes that succeed keep one shared garden, take access past the main house rather than from the street, and are modest against the host building — single storey where the plot is overlooked, and set back from boundaries. On 2000s houses and apartments (14% of 1,550 homes), converting an integral garage or a rear ground floor is often approved more readily than a detached garden unit, because the ancillary relationship is self-evident.
Downham Old Town contains the DOWNHAM MARKET CONSERVATION AREA conservation area (DOWNHAM MARKET CONSERVATION AREA designated 1975), so materials, fenestration and roof form are assessed against the appraisal. Where Borough Council of King's Lynn and West Norfolk grants permission, it commonly attaches a condition tying occupation of the annexe to the main dwelling. That condition is not a problem to be avoided — it is usually the mechanism that makes approval possible, and we draft the application on that basis rather than pretending the annexe is something it is not.
We draw annexes across Downham Old Town. A few of the areas where multigenerational schemes come up most often:
Annexe and granny-flat drawings for DOWNHAM MARKET — conservation area designated in 1975 — planned to stay ancillary and drawn to Borough Council of King's Lynn and West Norfolk's policies.
Annexe and granny-flat drawings for Downham Market — civil parish within Downham Old Town — planned to stay ancillary and drawn to Borough Council of King's Lynn and West Norfolk's policies.
Three similar buildings, three different consents. This is what separates them.
| What you build | Planning status | Key test | What Borough Council of King's Lynn and West Norfolk checks |
|---|---|---|---|
| Garden room, no sleeping space | Often Class E permitted development | Incidental to the house | Height, footprint, boundary position |
| Annexe used by the household | Full application, usually with a tie condition | Ancillary use | Shared garden and access, layout |
| Self-contained unit, own access | New dwelling — full application | Separate planning unit | Policy on new homes, amenity, parking |
| Converted garage or ground floor | Often permitted, use still assessed | Whether use changes | Independence of the accommodation |
| Annexe on designated land | Full application | Designation | Character and appearance |
The ancillary/separate-dwelling distinction comes from section 55 of the Town and Country Planning Act 1990; outbuilding limits from the GPDO 2015, Schedule 2, Part 1, Class E.
A fixed process built around how Borough Council of King's Lynn and West Norfolk tests the use question as well as the design.
Tell us who the annexe is for and where it would sit on the plot. We confirm designation status and tell you honestly whether the scheme reads as ancillary or as a separate dwelling in Downham Old Town.
We measure the plot, the existing house and the access route, so the shared-garden and shared-access case can be drawn rather than asserted.
Chartered designers develop the annexe to your brief, with the layout, access and garden relationship arranged to support the ancillary case under Borough Council of King's Lynn and West Norfolk's policies.
We submit the application with a supporting statement on use, manage validation and case-officer queries, and revise free until Borough Council of King's Lynn and West Norfolk decides.
Almost always. Sleeping accommodation is generally not "incidental" to the enjoyment of a house, so it falls outside the outbuilding permitted-development right, and any annexe that could function independently raises a change-of-use question under section 55. In Downham Old Town we prepare a full application to Borough Council of King's Lynn and West Norfolk and make the ancillary case explicitly rather than hoping it is not asked.
A shared garden rather than a divided one, access through the main property rather than a separate street entrance, occupation by a member of the same household, and a physical and functional relationship with the main house. Borough Council of King's Lynn and West Norfolk weighs those together — no single feature decides it, but a separate front door and a fenced-off garden together usually settle it against you. This applies to your Downham Old Town address specifically.
Yes, subject to permission. A detached garden annexe is assessed on its scale against the plot, its effect on neighbours and the character of the area, and then on the use question. Keeping it single storey, set in from boundaries and served off the shared garden gives it the best prospect in Downham Old Town, particularly near designated areas such as DOWNHAM MARKET CONSERVATION AREA. Borough Council of King's Lynn and West Norfolk is the decision-maker.
Commonly, yes — a condition tying occupation of the annexe to the main dwelling, so it cannot be sold or let separately. That is normally what makes approval possible, because it removes the concern that a new independent home is being created without going through housing policy. The condition runs with the land, so it matters at resale, and we explain the implications before you commit. This applies to your Downham Old Town address specifically. Borough Council of King's Lynn and West Norfolk is the decision-maker.
Yes. A new annexe is new habitable accommodation, so structure, fire escape, insulation and ventilation all apply, and a detached annexe close to a boundary raises fire-spread requirements as well. Planning and building control are separate consents with separate submissions — we prepare both so the approved design is the one that can actually be built. This applies to your Downham Old Town address specifically. Borough Council of King's Lynn and West Norfolk is the decision-maker.
A householder application runs to an eight-week statutory target; where the council treats the annexe as creating a new unit it becomes a minor application with a thirteen-week target instead. Which route applies depends on how the use is characterised, which is precisely why the ancillary case is worth making properly at the outset. This applies to your Downham Old Town address specifically. Borough Council of King's Lynn and West Norfolk is the decision-maker.
We quote each Downham Old Town annexe individually, because plot, access and whether you are converting or building new all change the work, and send a fixed, no-obligation quote within one working day. It covers the full drawing pack and supporting statement, with free revisions until Borough Council of King's Lynn and West Norfolk 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.