Dormer, hip-to-gable and mansard loft conversion drawings for St Mary's homes — prepared to Adur District Council's design guidance, delivered in days and revised free until your decision lands, with a free approval-odds score first.
Adur District Council granted 96% of the householder planning decisions it made in its latest published year — 9 points above the 87% England-wide householder average. St Mary's contains Shoreham-by-Sea, Southlands conservation areas (Shoreham-by-Sea designated 1971), 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), 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. St Mary's carries at least one Article 4 direction, and conservation areas including Shoreham-by-Sea and Southlands remove those rights outright, so we confirm your exact address before a line is drawn. A validated householder application in St Mary's is determined against an 8-week statutory target.
Shoreham-by-Sea (conservation area designated in 1971) and Southlands (conservation area designated in 1993) — these are the St Mary's pockets our drawings cover most. Heritage designations here include Shoreham-by-Sea and Southlands. Adur District Council weighs each proposal against the adopted Adur local plan and Adur District Council's design guidance for householder work, where the 2,480 homes here are 14% pre-1900, 13% 1930-1939, 10% 1965-1972, 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 hipped roofs with shallow pitches typical of 1930s building, over Victorian and earlier houses (14% of 2,480 homes), 1930s semi-detached and detached houses (13%) and late-1960s and early-1970s houses (10%).
Before anything is drawn we check your address against the designations that apply in St Mary's: Shoreham-by-Sea (conservation area designated in 1971) and Southlands (conservation area designated in 1993). Inside those boundaries permitted development is curtailed and Adur 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.
Adur District Council has 9 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 St Mary's.
On stock, St Mary's is Victorian and earlier houses (14% of 2,480 homes), 1930s semi-detached and detached houses (13%) and late-1960s and early-1970s houses (10%) — which is why steeply pitched slate roofs, valley gutters and party parapets typical of pre-1900 building and hipped roofs with shallow pitches typical of 1930s building govern what a loft or rear projection can realistically be. Adur District Council decided 210 householder applications in the latest published year and granted 96%, with 60% issued inside the eight-week target. That decision record, not a national figure, is what we design to.
The full build-period split for St Mary's runs pre-1900 14% (350 homes), 1900-1918 7% (180 homes), 1919-1929 10% (240 homes), 1930-1939 13% (330 homes), 1945-1954 2% (50 homes), 1955-1964 4% (90 homes), 1965-1972 10% (250 homes), 1973-1982 5% (120 homes), 1983-1992 3% (80 homes), 1993-1999 4% (100 homes) and 2000-2008 9% (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.
Adur District Council also decides for Manor and Southwick Green, so a decision in St Mary's 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 Southdown Road, Southwick, Church Street, Shoreham-by-Sea, Kingston Buci Conservation Area and Land adjoining Steyning Road, Shoreham-by-Sea. 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 St Mary's and Adur 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 | St Mary's |
|---|---|
| Dwellings recorded | 2,480 |
| Built pre-1900 | 350 (14%) |
| Built 1900-1918 | 180 (7%) |
| Built 1919-1929 | 240 (10%) |
| Built 1930-1939 | 330 (13%) |
| Built 1945-1954 | 50 (2%) |
| Built 1955-1964 | 90 (4%) |
| Built 1965-1972 | 250 (10%) |
| Built 1973-1982 | 120 (5%) |
| Built 1983-1992 | 80 (3%) |
| Built 1993-1999 | 100 (4%) |
| Built 2000-2008 | 220 (9%) |
| Built before 1919 | 21% |
| Built 1919–1939 | 23% |
| Built 1945–2008 | 37% |
| Conservation areas in St Mary's | 2 (Shoreham-by-Sea, Southlands) |
| Conservation areas district-wide | 7 |
| Article 4 directions recorded | 9 |
| Householder applications decided | 210 |
| Householder applications granted | 96% |
| Decided within 8 weeks | 60% |
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 Adur District Council's own, from MHCLG live table PS2 for the year to 31 March 2026.
St Mary's's roofs set the brief. The borough is built largely from Victorian and earlier houses (14% of 2,480 homes), 1930s semi-detached and detached houses (13%) and late-1960s and early-1970s houses (10%), and its lofts sit under steeply pitched slate roofs, valley gutters and party parapets typical of pre-1900 building and hipped roofs with shallow pitches typical of 1930s building — the geometry that decides whether a rear dormer, a hip-to-gable or a mansard gives you the headroom you want. Adur District Council assesses loft proposals against the adopted Adur local plan and Adur District Council's design guidance for householder work, 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 Adur District Council can verify them. St Mary's contains Shoreham-by-Sea, Southlands conservation areas (Shoreham-by-Sea designated 1971), 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.
St Mary's also carries protected streets — Shoreham-by-Sea and Southlands among them. Adur District Council has 9 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 St Mary's. We check your address against those designations before a line is drawn.
Many St Mary's 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 Adur 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 Adur 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 Adur District Council's real householder decision record, pulled from official planning statistics and updated as new data lands. Adur District Council granted 96% of its householder applications in the year to 31 March 2026, and Shoreham-by-Sea 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 Shoreham-by-Sea and Southlands, 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 hipped roofs with shallow pitches typical of 1930s building, a hip-to-gable followed by a rear dormer unlocks far more space, though it needs a full application.
The 2,480 homes here are 14% pre-1900, 13% 1930-1939, 10% 1965-1972, 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 Adur 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 St Mary's roofs come up most often:
Loft conversion drawings for Shoreham-by-Sea's conservation area designated in 1971 — measured, volume-checked and drawn to Adur District Council's guidance.
Loft conversion drawings for Southlands's conservation area designated in 1993 — measured, volume-checked and drawn to Adur District Council's guidance.
The right loft in St Mary's 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 Adur 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 Shoreham-by-Sea and Southlands and Article 4 directions can remove permitted-development rights.
A fixed process built around how Adur District Council validates and decides householder loft applications — most drawings are submission-ready within seven days of survey.
Tell us your St Mary's 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 Adur 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 Adur District Council's roof-alteration guidance.
We submit the certificate or application, manage validation and case-officer queries, and revise the drawings free until Adur 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 St Mary's the main exceptions are hip-to-gable conversions, dormers visible from the highway, and homes in conservation areas such as Shoreham-by-Sea and Southlands or on streets with an Article 4 direction. Adur District Council is the decision-maker.
Generally no. In conservation areas including Shoreham-by-Sea and Southlands, Class B permitted-development rights for lofts are removed, so a rear dormer that would be lawful elsewhere needs a full application to Adur District Council. Adur District Council has 9 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 St Mary's. We check your exact address before drawing.
On steeply pitched slate roofs, valley gutters and party parapets typical of pre-1900 building, common across St Mary's, a rear dormer is usually the most efficient conversion and often permitted development. Where the roof is hipped roofs with shallow pitches typical of 1930s 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. Adur District Council is the decision-maker.
A householder planning application in St Mary's 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. Adur District Council is the decision-maker.
If your dormer is permitted development, a lawful development certificate from Adur 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 St Mary's address specifically.
Every roof is different, so we quote each St Mary's project individually — a fixed, no-obligation price back within one working day. The quote covers the full drawing pack with free revisions until Adur 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.