
Rear dormer drawings for Heavitree roofs — the box across the back slope that turns a low attic into a full-height room, drawn to Exeter City Council's guidance and the volume limits, delivered in days and revised free until your decision, with a free approval-odds check first.
Exeter City Council granted 87% of the householder planning decisions it made in its latest published year — level with the 87% England-wide householder average. The Heavitree conservation area protects the old village core, so frontage, shopfront and roofline changes around Fore Street are assessed on design, which is where a policy-literate drawing pack earns its keep. Its dominant Victorian (1837–1901), Edwardian (1901–1910), interwar (1918–1939) and postwar (1945–1970) housing stock sets the design brief on most streets.
The permitted-development ceilings are fixed: 40m³ of new roof volume for a terraced loft and 50m³ for a semi or detached house under Class B, plus a 3m single-storey rear extension on a terrace or 4m on a detached house under Class A. In conservation areas such as Heavitree, Mount Radford and St Leonard's those rights are removed, so we confirm your exact address before a line is drawn. A validated householder application in Heavitree is determined against an 8-week statutory target.
Fore Street (the old village high street around the Gordon Lamp and Livery Dole), Magdalen Road (Victorian terraces and shops linking Heavitree to St Leonard's), Polsloe (Edwardian and interwar terraces near Polsloe Bridge station), Whipton (interwar and postwar semis on the eastern edge) and Livery Dole (listed sixteenth-century almshouses and chapel on Magdalen Road) — these are the Heavitree pockets our drawings cover most. Heritage designations here include Heavitree, Mount Radford and St Leonard's. Exeter City Council weighs each proposal against the Exeter Local Plan / Core Strategy and the emerging Exeter Plan, where the local red Heavitree breccia and slate that give the suburb its character steer material choices on extensions in the older streets. On roofs the borough is gabled Welsh-slate roofs on the bay-fronted terraces and hipped roofs on the interwar semis, over Victorian and Edwardian bay-fronted terraces, period cottages and villas in local red Heavitree breccia and interwar and postwar suburban semis on the fringes.
The box dormer is the workhorse loft, and most of Heavitree is built for it — the borough runs to Victorian and Edwardian bay-fronted terraces, period cottages and villas in local red Heavitree breccia and interwar and postwar suburban semis on the fringes under gabled Welsh-slate roofs on the bay-fronted terraces and hipped roofs on the interwar semis, and a flat-roofed box across the rear slope is the cheapest cubic metre of full-height space those roofs give up. Exeter City Council tests the dormer against the Exeter Local Plan / Core Strategy and the emerging Exeter Plan, 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. The Heavitree conservation area protects the old village core, so frontage, shopfront and roofline changes around Fore Street are assessed on design, so the cheeks, the window line and the material are drawn to answer it rather than invite a query.
Where Heavitree's streets are protected — Heavitree, Mount Radford and St Leonard's among them — the Class B dormer right is switched off and even a modest rear box needs consent. Heavitree sits outside the city's HMO Article 4 Direction, but the Heavitree conservation area — with the listed Livery Dole almshouses and St Clare's Chapel at its heart — and the neighbouring Mount Radford area remove permitted-development rights on many of its older streets. We confirm the designation before the box is sized.

Many rear dormers in Heavitree are permitted development, but the volume and position decide it. You will normally need a full application to Exeter City Council if any of these apply:
We draw the box within its volume allowance, the flat roof below the ridge and the face set back off the eaves — the three things a dormer stands or falls on — and submit a validation-complete pack, whether that is a lawful development certificate or a full householder application.
Below is Exeter City Council's real householder decision record, drawn from official planning statistics and refreshed as new data lands. Exeter grants around 87% of the applications it decides, with the tight rhythm of Heavitree's bay-fronted terraces and its village-core conservation area the main constraints on rear and roof schemes. A dormer is decided on volume and set-back, so a pack that shows the calculation and the eaves detail is cleared 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 Fore Street, Magdalen Road and Polsloe, the dormer that goes through is the subordinate rear box: flat roof kept low, cheeks clad to recede, side windows obscure-glazed against overlooking, and the whole thing set back so the original eaves line still reads from the garden. On gabled Welsh-slate roofs on the bay-fronted terraces, this returns a full-height double and en-suite from what was standing-room-only, usually inside the permitted-development volume.
The local red Heavitree breccia and slate that give the suburb its character steer material choices on extensions in the older streets. We keep the box off the ridge, match the cheek material to the roof, and where the volume is already spent — or the street is designated — draw the dormer as a householder application composed to Exeter City Council's roof-alteration guidance rather than push a certificate that would be refused.

We draw rear dormers on the terraced and semi-detached streets across the borough. A few of the neighbourhoods where Heavitree dormers come up most often:
Dormer loft drawings for Fore Street's the old village high street around the Gordon Lamp and Livery Dole — volume-checked, set-back-detailed and drawn to Exeter City Council's guidance.
Dormer loft drawings for Magdalen Road's Victorian terraces and shops linking Heavitree to St Leonard's — volume-checked, set-back-detailed and drawn to Exeter City Council's guidance.
Dormer loft drawings for Polsloe's Edwardian and interwar terraces near Polsloe Bridge station — volume-checked, set-back-detailed and drawn to Exeter City Council's guidance.
Dormer loft drawings for Whipton's interwar and postwar semis on the eastern edge — volume-checked, set-back-detailed and drawn to Exeter City Council's guidance.
Dormer loft drawings for Livery Dole's listed sixteenth-century almshouses and chapel on Magdalen Road — volume-checked, set-back-detailed and drawn to Exeter City Council's guidance.
Whether a dormer in Heavitree needs permission comes down to where it sits and how big the box is. This is how the cases compare.
| Dormer type | Permitted development? | What it gains | What Exeter City Council checks |
|---|---|---|---|
| Rear box, within volume | Usually yes | Full-height room across the back | Volume total, 20cm eaves set-back |
| Rear box, over volume limit | No — full application | A larger room | How far over the allowance, bulk |
| Front or side dormer | No — full application | Light to the front rooms | Visibility from the street, character |
| Dormer in a conservation area | No — full application | Same space, extra scrutiny | Roof form and street appearance |
In conservation areas such as Heavitree and Mount Radford, Class B dormer rights are removed and every dormer needs a full application.
A fixed process built around how Exeter City Council validates and decides dormer applications — most drawings are submission-ready within seven days of survey.
Send us your Heavitree postcode and roof type. We confirm your conservation and Article 4 status, work out how much permitted-development volume you have left, and score your odds against live Exeter City Council decisions.
We measure ridge and eaves heights, roof pitch and the existing loft floor — the numbers the volume calculation, the set-back and the head heights depend on.
Chartered designers develop the box to your brief, drawn inside the Class B volume limits or, where those are exhausted or removed, to Exeter City Council's roof-alteration guidance.
We submit the certificate or application, manage validation and case-officer queries, and revise the drawings free until Exeter City Council issues its decision.
Often not. A rear box dormer within 40 cubic metres on a terrace, or 50 on a semi or detached house, set back at least 20 centimetres from the eaves and kept below the ridge, is usually permitted development. In Heavitree you will need a full application to Exeter City Council for a front or side dormer, a box that exceeds the volume, and any dormer in a conservation area such as Heavitree and Mount Radford, where those rights are removed.
The permitted-development limit is a volume, not a footprint: 40 cubic metres of added roof space on a terraced house and 50 on a semi-detached or detached one, and any earlier loft enlargement counts against that total. In Heavitree the box must also sit below the ridge and back from the eaves. We measure your roof and calculate the exact volume you have left before drawing. Exeter City Council is the decision-maker.
Not under permitted development. A dormer on the front roof slope, or one facing a highway, always needs a full application to Exeter City Council, because it changes how the house reads from the street. Rear box dormers are far more likely to be approved — or to be permitted development outright — which is why almost every Heavitree dormer we draw sits on the back slope.
Often, on a terrace or semi. If the dormer or the loft steelwork meets the party wall with your neighbour, the Party Wall etc. Act applies and notice must be served before work starts — separately from Exeter City Council's planning decision. We flag the party-wall junction on the drawings so a surveyor can be appointed early and the build is not held up. This applies to your Heavitree address specifically.
If your dormer is permitted development, a lawful development certificate from Exeter City Council is council-stamped proof of it — worth holding, because a buyer's solicitor will ask for it when you sell. We prepare and submit the certificate with the same measured drawing pack that shows the box within its volume allowance. This applies to your Heavitree address specifically.
We price each Heavitree dormer individually, because the roof pitch and the volume left vary house to house, and send a fixed, no-obligation quote within one working day. It covers the full drawing pack with free revisions until Exeter City Council approves, and we confirm at the outset whether your box is permitted development or needs an application. Call 020 7864 7245 to start.
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