Dormer, hip-to-gable and mansard loft conversion drawings for Fordham & Isleham homes — prepared to East Cambridgeshire District Council's design guidance, delivered in days and revised free until your decision lands, with a free approval-odds score first.
East Cambridgeshire District Council granted 89% of the householder planning decisions it made in its latest published year — 2 points above the 87% England-wide householder average. Fordham & Isleham contains Chippenham, Fordham, Isleham conservation areas (Chippenham 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) 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. Fordham & Isleham carries at least one Article 4 direction, and conservation areas including Chippenham, Fordham and Isleham remove those rights outright, so we confirm your exact address before a line is drawn. A validated householder application in Fordham & Isleham is determined against an 8-week statutory target.
Chippenham (conservation area designated in 1975), Fordham (conservation area designated in 1975), Isleham (conservation area designated in 1975), Snailwell (conservation area designated in 1991), Chippenham (civil parish within Fordham & Isleham), Fordham (civil parish within Fordham & Isleham), Isleham (civil parish within Fordham & Isleham), Kennett (civil parish within Fordham & Isleham) and Snailwell (civil parish within Fordham & Isleham) — these are the Fordham & Isleham pockets our drawings cover most. Heritage designations here include Chippenham, Fordham, Isleham and Snailwell. East Cambridgeshire District Council weighs each proposal against East Cambridgeshire District Council's development plan and the design policies it applies to householder applications, where the 3,350 homes here are 15% pre-1900, 10% 1993-1999, 7% 1973-1982, 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 1990s building, over Victorian and earlier houses (15% of 3,350 homes), 1990s estate houses (10%) and 1970s and early-1980s houses (7%).
What is permitted in Fordham & Isleham turns on designation first, so that is where we start: Chippenham (conservation area designated in 1975), Fordham (conservation area designated in 1975), Isleham (conservation area designated in 1975) and Snailwell (conservation area designated in 1991). Inside those boundaries permitted development is curtailed and East Cambridgeshire District 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, Fordham & Isleham takes in Chippenham, Fordham, Isleham, Kennett and Snailwell. East Cambridgeshire District Council has 292 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 Fordham & Isleham.
On stock, Fordham & Isleham is Victorian and earlier houses (15% of 3,350 homes), 1990s estate houses (10%) and 1970s and early-1980s houses (7%) — which is why steeply pitched slate roofs, valley gutters and party parapets typical of pre-1900 building and trussed-rafter roofs typical of 1990s building govern what a loft or rear projection can realistically be. East Cambridgeshire District Council decided 354 householder applications in the latest published year and granted 89%, with 76% issued inside the eight-week target. We draw to that record rather than to a national average.
The full build-period split for Fordham & Isleham runs pre-1900 15% (500 homes), 1900-1918 3% (100 homes), 1919-1929 2% (70 homes), 1930-1939 6% (200 homes), 1945-1954 7% (220 homes), 1955-1964 5% (180 homes), 1965-1972 7% (240 homes), 1973-1982 7% (250 homes), 1983-1992 7% (250 homes), 1993-1999 10% (340 homes) and 2000-2008 6% (190 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.
East Cambridgeshire District Council also decides for Burwell, Downham Villages, Haddenham, Soham South, Stretham, Sutton, Bottisham and Woodditton, so a decision in Fordham & Isleham 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 1 & 19 Castlehythe, Ely, 1 & 2 Stonefields Cottages, Mill Lane, Burwell, 1 Barton Road, Ely and 1 Brook Dam Lane, Soham. 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 Fordham & Isleham and East Cambridgeshire District Council. These are the numbers that decide what is realistic on your street, so we work from them rather than from national averages.
| Measure | Fordham & Isleham |
|---|---|
| Dwellings recorded | 3,350 |
| Built pre-1900 | 500 (15%) |
| Built 1900-1918 | 100 (3%) |
| Built 1919-1929 | 70 (2%) |
| Built 1930-1939 | 200 (6%) |
| Built 1945-1954 | 220 (7%) |
| Built 1955-1964 | 180 (5%) |
| Built 1965-1972 | 240 (7%) |
| Built 1973-1982 | 250 (7%) |
| Built 1983-1992 | 250 (7%) |
| Built 1993-1999 | 340 (10%) |
| Built 2000-2008 | 190 (6%) |
| Built before 1919 | 18% |
| Built 1919–1939 | 8% |
| Built 1945–2008 | 50% |
| Conservation areas in Fordham & Isleham | 4 (Chippenham, Fordham…) |
| Conservation areas district-wide | 28 |
| Article 4 directions recorded | 292 |
| Householder applications decided | 354 |
| Householder applications granted | 89% |
| Decided within 8 weeks | 76% |
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 East Cambridgeshire District Council's own, from MHCLG live table PS2 for the year to 31 March 2026.
Fordham & Isleham's roofs set the brief. The borough is built largely from Victorian and earlier houses (15% of 3,350 homes), 1990s estate houses (10%) and 1970s and early-1980s houses (7%), and its lofts sit under steeply pitched slate roofs, valley gutters and party parapets typical of pre-1900 building and trussed-rafter roofs typical of 1990s building — the geometry that decides whether a rear dormer, a hip-to-gable or a mansard gives you the headroom you want. East Cambridgeshire District Council assesses loft proposals against East Cambridgeshire District Council's development plan and the design policies it applies to householder applications, and its case officers read each roof against the pair next door and the wider street before they read the plans.
That makes drawing quality decisive. We measure ridge and eaves heights, roof pitch and the existing stair, calculate the added volume against the permitted-development limits exactly, and show the workings on the drawings so East Cambridgeshire District Council can verify them. Fordham & Isleham contains Chippenham, Fordham, Isleham conservation areas (Chippenham designated 1975), so materials, fenestration and roof form are assessed against the appraisal, so we resolve it on the page rather than leave it for the case officer to raise.
Fordham & Isleham also carries protected streets — Chippenham, Fordham, Isleham and Snailwell among them. East Cambridgeshire District Council has 292 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 Fordham & Isleham. We check your address against those designations before a line is drawn.
Many Fordham & Isleham loft conversions proceed without planning permission — a rear dormer within the permitted-development volume limits (40 cubic metres on a terrace, 50 on a semi or detached house) is usually lawful. You will normally need a full application to East Cambridgeshire District Council if any of these apply:
We draw the roof line, the ridge height and the neighbour's daylight on the page — the relationships East Cambridgeshire District Council's officers check first — and submit a validation-complete pack, whether that is a lawful development certificate or a full householder application.
Below is East Cambridgeshire District Council's real householder decision record, pulled from official planning statistics and updated as new data lands. East Cambridgeshire District Council granted 89% of its householder applications in the year to 31 March 2026, and Chippenham shapes what is approved here. Professionally prepared loft drawings anticipate those pressure points before submission, which is why complete, policy-literate packs are decided faster and refused less often than DIY applications.
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 Chippenham, Fordham and Isleham, the recurring loft is the rear dormer — a box across the back roof slope that turns a cramped attic into a full-height double bedroom and en-suite. On steeply pitched slate roofs, valley gutters and party parapets typical of pre-1900 building, that is usually the most efficient use of the roof; where the stock is trussed-rafter roofs typical of 1990s building, a hip-to-gable followed by a rear dormer unlocks far more space, though it needs a full application.
The 3,350 homes here are 15% pre-1900, 10% 1993-1999, 7% 1973-1982, which is what sets the realistic roof and rear-projection options. We draw the dormer inside the volume allowance, keep the flat-roof build-up below the ridge, and set the face back from the eaves as the rules require — so the pack answers East Cambridgeshire District Council's questions before they are asked. Where permitted-development rights are exhausted or removed, we prepare a householder application composed to the borough's roof-alteration guidance instead.
We draw loft conversions on every street in the borough. A few of the neighbourhoods where Fordham & Isleham roofs come up most often:
Loft conversion drawings for Chippenham's conservation area designated in 1975 — measured, volume-checked and drawn to East Cambridgeshire District Council's guidance.
Loft conversion drawings for Fordham's conservation area designated in 1975 — measured, volume-checked and drawn to East Cambridgeshire District Council's guidance.
Loft conversion drawings for Isleham's conservation area designated in 1975 — measured, volume-checked and drawn to East Cambridgeshire District Council's guidance.
Loft conversion drawings for Snailwell's conservation area designated in 1991 — measured, volume-checked and drawn to East Cambridgeshire District Council's guidance.
Loft conversion drawings for Chippenham's civil parish within Fordham & Isleham — measured, volume-checked and drawn to East Cambridgeshire District Council's guidance.
Loft conversion drawings for Fordham's civil parish within Fordham & Isleham — measured, volume-checked and drawn to East Cambridgeshire District Council's guidance.
The right loft in Fordham & Isleham depends on your roof. This is how the main types compare on planning route and the space they add.
| Loft type | Permitted development? | Space & headroom | What East Cambridgeshire District Council checks |
|---|---|---|---|
| Rear dormer | Usually yes, within volume limits | Full-height double room at the back | Volume, set-back from eaves, ridge height |
| Hip-to-gable | No — full application | Extends the whole side of the roof | Roof bulk and the symmetry of the pair |
| Mansard | No — full application | Maximum floor area across the roof | Street character, especially in conservation areas |
| Rooflights only | Usually yes (Class C) | Light and headroom, no extra footprint | Whether rooflights sit within the existing slope |
Route depends on your street — conservation areas such as Chippenham and Fordham and Article 4 directions can remove permitted-development rights.
A fixed process built around how East Cambridgeshire District Council validates and decides householder loft applications — most drawings are submission-ready within seven days of survey.
Tell us your Fordham & Isleham postcode and roof type. We confirm your conservation and Article 4 status, how much permitted-development volume you have left, and score your odds against live East Cambridgeshire District Council decisions.
We measure ridge and eaves heights, roof pitch, joist levels and the existing stair — the numbers the volume calculation and head heights depend on.
Chartered designers develop the dormer, hip-to-gable or mansard to your brief, drawn inside the Class B limits or to East Cambridgeshire District Council's roof-alteration guidance.
We submit the certificate or application, manage validation and case-officer queries, and revise the drawings free until East Cambridgeshire District Council issues its decision.
Often not. A rear dormer within 40 cubic metres on a terrace, or 50 on a semi-detached or detached house, set back from the eaves and no higher than the ridge, is usually permitted development. In Fordham & Isleham the main exceptions are hip-to-gable conversions, dormers visible from the highway, and homes in conservation areas such as Chippenham and Fordham or on streets with an Article 4 direction. East Cambridgeshire District Council is the decision-maker.
Generally no. In conservation areas including Chippenham and Fordham, Class B permitted-development rights for lofts are removed, so a rear dormer that would be lawful elsewhere needs a full application to East Cambridgeshire District Council. East Cambridgeshire District Council has 292 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 Fordham & Isleham. We check your exact address before drawing.
On steeply pitched slate roofs, valley gutters and party parapets typical of pre-1900 building, common across Fordham & Isleham, a rear dormer is usually the most efficient conversion and often permitted development. Where the roof is trussed-rafter roofs typical of 1990s building, a hip-to-gable followed by a rear dormer gains far more usable space but needs planning permission. Our survey confirms which your roof supports before we draw. East Cambridgeshire District Council is the decision-maker.
A householder planning application in Fordham & Isleham runs to a statutory eight-week target, and a lawful development certificate to eight weeks as well, though validation can add time if the pack is incomplete. We submit validation-complete drawings and manage case-officer queries to keep the decision on track. East Cambridgeshire District Council is the decision-maker.
If your dormer is permitted development, a lawful development certificate from East Cambridgeshire District Council is council-stamped proof of that — worth having, because every buyer's solicitor will ask for it when you sell. We prepare and submit the certificate application with the same drawing pack. This applies to your Fordham & Isleham address specifically.
Every roof is different, so we quote each Fordham & Isleham project individually — a fixed, no-obligation price back within one working day. The quote covers the full drawing pack with free revisions until East Cambridgeshire District Council approves, and we tell you upfront whether your loft qualifies as permitted development. 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.