Dormer loft conversion plans in Eynsham and Cassington

Eynsham and Cassington planning decisions and design rules

West Oxfordshire District Council granted 97% of the householder planning decisions it made in its latest published year — 10 points above the 87% England-wide householder average. Eynsham and Cassington contains Cassington Conservation Area, Eynsham Conservation Area conservation areas (Cassington Conservation Area designated 1992), 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.

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. Eynsham and Cassington carries at least one Article 4 direction, and conservation areas including Cassington Conservation Area and Eynsham Conservation Area remove those rights outright, so we confirm your exact address before a line is drawn. A validated householder application in Eynsham and Cassington is determined against an 8-week statutory target.

Cassington (conservation area designated in 1992), Eynsham (conservation area designated in 1975), South Leigh and High Cogges (civil parish within Eynsham and Cassington), Cassington (civil parish within Eynsham and Cassington) and Eynsham (civil parish within Eynsham and Cassington) — these are the Eynsham and Cassington pockets our drawings cover most. Heritage designations here include Cassington Conservation Area and Eynsham Conservation Area. West Oxfordshire District Council weighs each proposal against West Oxfordshire District Council's development plan and the design policies it applies to householder applications, where the 3,040 homes here are 18% 1965-1972, 15% pre-1900, 15% 1955-1964, which is what sets the realistic roof and rear-projection options. On roofs the borough is shallow-pitched roofs and integral garages typical of that period's building and steeply pitched slate roofs, valley gutters and party parapets typical of pre-1900 building, over late-1960s and early-1970s houses (18% of 3,040 homes), Victorian and earlier houses (15%) and late-1950s and early-1960s houses (15%).

Why a Eynsham and Cassington scheme is judged on Eynsham and Cassington terms

What is permitted in Eynsham and Cassington turns on designation first, so that is where we start: Cassington (conservation area designated in 1992) and Eynsham (conservation area designated in 1975). Inside those boundaries permitted development is curtailed and West Oxfordshire 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, Eynsham and Cassington takes in South Leigh and High Cogges, Cassington and Eynsham. West Oxfordshire District Council has 84 recorded Article 4 directions, removing permitted development for painting the exterior and gates, walls and fences — check the address before assuming PD applies in Eynsham and Cassington.

On stock, Eynsham and Cassington is late-1960s and early-1970s houses (18% of 3,040 homes), Victorian and earlier houses (15%) and late-1950s and early-1960s houses (15%) — which is why shallow-pitched roofs and integral garages typical of that period's building and steeply pitched slate roofs, valley gutters and party parapets typical of pre-1900 building govern what a loft or rear projection can realistically be. West Oxfordshire District Council decided 616 householder applications in the latest published year and granted 97%, with 75% issued inside the eight-week target. We draw to that record rather than to a national average.

The full build-period split for Eynsham and Cassington runs pre-1900 15% (470 homes), 1900-1918 1% (20 homes), 1919-1929 3% (100 homes), 1930-1939 3% (100 homes), 1945-1954 4% (130 homes), 1955-1964 15% (470 homes), 1965-1972 18% (560 homes), 1973-1982 5% (160 homes), 1983-1992 10% (300 homes), 1993-1999 4% (110 homes) and 2000-2008 3% (80 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.

West Oxfordshire District Council also decides for Alvescot and Filkins, Ascott and Shipton, Bampton and Clanfield, Ducklington, Milton-under-Wychwood, The Bartons, Witney Central and Woodstock and Bladon, so a decision in Eynsham and Cassington 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 Article 4 ((Little Rollright), Article 4 (Cassington), Article 4 (Charlbury 1) and Article 4 (Crawley 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.

The rear dormer, drawn for Eynsham and Cassington roofs

The box dormer is the workhorse loft, and most of Eynsham and Cassington is built for it — the borough runs to late-1960s and early-1970s houses (18% of 3,040 homes), Victorian and earlier houses (15%) and late-1950s and early-1960s houses (15%) under shallow-pitched roofs and integral garages typical of that period's building and steeply pitched slate roofs, valley gutters and party parapets typical of pre-1900 building, and a flat-roofed box across the rear slope is the cheapest cubic metre of full-height space those roofs give up. West Oxfordshire District Council tests the dormer against West Oxfordshire District Council's development plan and the design policies it applies to householder applications, and because permitted development turns on a number, the volume you propose against the volume you have left is the first thing an officer or a certificate checks.

That is why the arithmetic goes on the drawings. We calculate the box against the 40- or 50-cubic-metre allowance, count any earlier roof enlargement into the total, hold the flat roof below the ridge and set the face back off the eaves so the dormer reads as subordinate. Eynsham and Cassington contains Cassington Conservation Area, Eynsham Conservation Area conservation areas (Cassington Conservation Area designated 1992), so materials, fenestration and roof form are assessed against the appraisal, so the cheeks, the window line and the material are drawn to answer it rather than invite a query.

Where Eynsham and Cassington's streets are protected — Cassington Conservation Area and Eynsham Conservation Area among them — the Class B dormer right is switched off and even a modest rear box needs consent. West Oxfordshire District Council has 84 recorded Article 4 directions, removing permitted development for painting the exterior and gates, walls and fences — check the address before assuming PD applies in Eynsham and Cassington. We confirm the designation before the box is sized.