Dormer, hip-to-gable and mansard loft conversion drawings for Lewisham homes — prepared to Lewisham Council's design guidance, delivered in days and revised free until your decision lands, with a free approval-odds score first.
Lewisham Council granted 90% of the householder planning decisions it made in its latest published year — 3 points above the 87% England-wide householder average. Policies resist the loss of family-sized houses, so conversions to flats face an added hurdle, which is where a policy-literate drawing pack earns its keep. Its dominant Georgian (1714–1837), Victorian (1837–1901) and Edwardian (1901–1910) housing stock sets the design brief on most streets.
Under Class B, a rear dormer stays permitted development up to 40m³ of added roof volume on a terrace or 50m³ on a semi-detached or detached house, while Class A allows a single-storey rear extension of 3m beyond the original rear wall on a terrace and 4m on a detached house before a full application is needed. Lewisham carries at least one Article 4 direction, and conservation areas including Blackheath, Telegraph Hill and Brockley remove those rights outright, so we confirm your exact address before a line is drawn. A validated householder application in Lewisham is determined against an 8-week statutory target.
Blackheath (grand villas and terraces on the Lewisham side of the heath), Brockley (long Victorian terraces within one of London's largest conservation areas), Telegraph Hill (hilly Victorian terraces framing the two parks), Deptford (Georgian survivals like Albury Street amid dense terraced streets), Forest Hill (Victorian villas and terraces stepping up the slopes) and Sydenham (Victorian terraces and semis toward the Crystal Palace ridge) — these are the Lewisham pockets our drawings cover most. Heritage designations here include Blackheath, Telegraph Hill, Brockley, Deptford High Street and Sydenham. Lewisham Council weighs each proposal against the Lewisham Local Plan and the borough's Alterations and Extensions SPD, where in the Brockley and Telegraph Hill conservation areas original slate roofs and front elevations are closely guarded. Brockley, Forest Hill and Deptford hold large numbers of houses long ago converted into flats and maisonettes, which carry no householder permitted-development rights.. On roofs the borough is London butterfly roofs on the Victorian terraces and gabled roofs on the villas, over Victorian terraces, Victorian and Edwardian villas and converted flats and maisonettes.
Lewisham's roofs set the brief. The borough is built largely from Victorian terraces, Victorian and Edwardian villas and converted flats and maisonettes, and its lofts sit under London butterfly roofs on the Victorian terraces and gabled roofs on the villas — the geometry that decides whether a rear dormer, a hip-to-gable or a mansard gives you the headroom you want. Lewisham Council assesses loft proposals against the Lewisham Local Plan and the borough's Alterations and Extensions SPD, 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 Lewisham Council can verify them. Policies resist the loss of family-sized houses, so conversions to flats face an added hurdle, so we resolve it on the page rather than leave it for the case officer to raise.
Lewisham also carries protected streets — Blackheath, Telegraph Hill, Brockley, Deptford High Street and Sydenham among them. Lewisham operates Article 4 directions in conservation areas such as Brockley alongside controls resisting the conversion of family houses into flats, so works that are permitted development elsewhere routinely need an application here. We check your address against those designations before a line is drawn.
Many Lewisham 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 Lewisham Council if any of these apply:
We draw the roof line, the ridge height and the neighbour's daylight on the page — the relationships Lewisham 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 Lewisham Council's real householder decision record, pulled from official planning statistics and updated as new data lands. Lewisham grants the large majority of householder applications, though its policy shielding family houses from conversion and its Victorian conservation areas shape roof and rear works street by street. 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, rolling year). 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 Blackheath, Brockley and Telegraph Hill, 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 London butterfly roofs on the Victorian terraces, that is usually the most efficient use of the roof; where the stock is gabled roofs on the villas, a hip-to-gable followed by a rear dormer unlocks far more space, though it needs a full application.
In the Brockley and Telegraph Hill conservation areas original slate roofs and front elevations are closely guarded. 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 Lewisham 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 Lewisham roofs come up most often:
Loft conversion drawings for Blackheath's grand villas and terraces on the Lewisham side of the heath — measured, volume-checked and drawn to Lewisham Council's guidance.
Loft conversion drawings for Brockley's long Victorian terraces within one of London's largest conservation areas — measured, volume-checked and drawn to Lewisham Council's guidance.
Loft conversion drawings for Telegraph Hill's hilly Victorian terraces framing the two parks — measured, volume-checked and drawn to Lewisham Council's guidance.
Loft conversion drawings for Deptford's Georgian survivals like Albury Street amid dense terraced streets — measured, volume-checked and drawn to Lewisham Council's guidance.
Loft conversion drawings for Forest Hill's Victorian villas and terraces stepping up the slopes — measured, volume-checked and drawn to Lewisham Council's guidance.
Loft conversion drawings for Sydenham's Victorian terraces and semis toward the Crystal Palace ridge — measured, volume-checked and drawn to Lewisham Council's guidance.
The right loft in Lewisham 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 Lewisham 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 Blackheath and Telegraph Hill and Article 4 directions can remove permitted-development rights.
A fixed process built around how Lewisham Council validates and decides householder loft applications — most drawings are submission-ready within seven days of survey.
Tell us your Lewisham 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 Lewisham 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 Lewisham Council's roof-alteration guidance.
We submit the certificate or application, manage validation and case-officer queries, and revise the drawings free until Lewisham 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 Lewisham the main exceptions are hip-to-gable conversions, dormers visible from the highway, and homes in conservation areas such as Blackheath and Telegraph Hill or on streets with an Article 4 direction. Lewisham Council is the decision-maker.
Generally no. In conservation areas including Blackheath and Telegraph Hill, Class B permitted-development rights for lofts are removed, so a rear dormer that would be lawful elsewhere needs a full application to Lewisham Council. Lewisham operates Article 4 directions in conservation areas such as Brockley alongside controls resisting the conversion of family houses into flats, so works that are permitted development elsewhere routinely need an application here. We check your exact address before drawing.
On London butterfly roofs on the Victorian terraces, common across Lewisham, a rear dormer is usually the most efficient conversion and often permitted development. Where the roof is gabled roofs on the villas, 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. Lewisham Council is the decision-maker.
A householder planning application in Lewisham 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. Lewisham Council is the decision-maker.
If your dormer is permitted development, a lawful development certificate from Lewisham 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.
Every roof is different, so we quote each Lewisham project individually — a fixed, no-obligation price back within one working day. The quote covers the full drawing pack with free revisions until Lewisham 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.