
Orangery and conservatory drawings for Lewisham homes — checked against the Class A rear limits and the 30m² building-regulations exemption, drawn to Lewisham Council's guidance and revised free until your decision.
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.
The difference is not marketing. A conservatory is predominantly glazed — at least three quarters of the roof and half of the walls — which is what earns it the building-regulations exemption. An orangery has a solid masonry perimeter with a glazed lantern set into a flat roof, so it usually reads as a conventional extension for building control and has to meet Part L thermal standards, Part A structure and Part B fire like any other room.
Both are judged the same way for planning: as rear extensions, against the Class A depth, height and eaves limits, and against the Lewisham Local Plan and the borough's Alterations and Extensions SPD. Lewisham is largely Victorian terraces, Victorian and Edwardian villas and converted flats and maisonettes, and the design question is usually whether the glazing reads as a lightweight addition to that stock or as a bolted-on conservatory kit. On period houses, an orangery with a properly proportioned lantern almost always sits better than a full-height glazed box.
In conservation areas such as Blackheath and Telegraph Hill, rear glazing is assessed on visibility from the street and on the effect on the rear elevation's character. 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.

Many conservatories are permitted development. You will need an application to Lewisham Council where any of these apply:
We check the scheme against the Class A planning limits and against the building-regulations exemption at the same time, so you know before committing whether you are building an exempt conservatory or a fully regulated room.
Below is Lewisham Council's real householder decision record, drawn from official planning statistics and refreshed 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. Glazed rear additions are judged on depth, eaves height and how the glazing meets the existing elevation.
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 schemes that succeed keep the eaves below the neighbour's ground-floor cill line, set the glazing back from the boundary, and use a solid parapet or brick perimeter to tie the addition into the house. On victorian terraces, a lantern set in a flat roof usually reads better than a pitched glazed roof, and it avoids the summer overheating that makes full conservatories unusable for months a year.
Policies resist the loss of family-sized houses, so conversions to flats face an added hurdle. The decision worth making early is whether to keep the separating doors. Keeping them preserves the building-regulations exemption but leaves you with a room that is not part of the house; removing them creates one continuous space but brings the whole addition inside Part L, which changes the glazing specification and usually the heating design too. We set out both versions before you commit.

We draw glazed rear additions across Lewisham. A few of the areas where they come up most often:
Orangery and conservatory drawings for Blackheath — grand villas and terraces on the Lewisham side of the heath — checked against the Class A limits and drawn to Lewisham Council's guidance.
Orangery and conservatory drawings for Brockley — long Victorian terraces within one of London's largest conservation areas — checked against the Class A limits and drawn to Lewisham Council's guidance.
Orangery and conservatory drawings for Telegraph Hill — hilly Victorian terraces framing the two parks — checked against the Class A limits and drawn to Lewisham Council's guidance.
Orangery and conservatory drawings for Deptford — Georgian survivals like Albury Street amid dense terraced streets — checked against the Class A limits and drawn to Lewisham Council's guidance.
Orangery and conservatory drawings for Forest Hill — Victorian villas and terraces stepping up the slopes — checked against the Class A limits and drawn to Lewisham Council's guidance.
Orangery and conservatory drawings for Sydenham — Victorian terraces and semis toward the Crystal Palace ridge — checked against the Class A limits and drawn to Lewisham Council's guidance.
The planning test is the same for both. The building-regulations test is not.
| Structure | Planning route | Building regulations | Practical effect |
|---|---|---|---|
| Conservatory under 30m², doors retained | Class A rear extension limits | Largely exempt | Cheaper build, unheated in winter |
| Conservatory, doors removed | Class A rear extension limits | Part L applies in full | Continuous space, higher spec glazing |
| Orangery with solid perimeter and lantern | Class A rear extension limits | Fully regulated | Usable year round, better on period houses |
| Any of the above beyond the depth limits | Full householder application | As above | 8-week determination |
| Any of the above on designated land | Full householder application | As above | Design and visibility assessed |
Planning limits from the GPDO 2015, Schedule 2, Part 1, Class A; exemption criteria from the Building Regulations 2010, Schedule 2, Class 7.
A fixed process covering both consents, because they pull in different directions.
Send us your Lewisham postcode and house type. We confirm the Class A limits that apply, check designation status, and score your odds against live Lewisham Council decisions.
We measure the rear elevation, eaves and ground levels, and the neighbouring boundary — the numbers that decide both the projection limit and the 2-metre eaves rule.
Chartered designers develop the orangery or conservatory to your brief, and we set out clearly whether it stays inside the building-regulations exemption or becomes a fully regulated room.
We submit the certificate or application, manage validation and officer queries, and revise free until Lewisham Council decides.
Often not. A conservatory is treated as a rear extension, so it can be permitted development within the Class A limits — 3 metres of projection on a terrace or semi, 4 metres on a detached house, with eaves under 3 metres where it sits within 2 metres of a boundary. In Lewisham you will need an application to Lewisham Council beyond those limits, and on designated land such as Blackheath and Telegraph Hill.
A conservatory is largely exempt if it is under 30 square metres, at ground level, separated from the house by external-quality doors, and has at least 75% of its roof and 50% of its walls glazed. Glazing, electrics and any drainage work still have to comply. Remove the separating doors and the exemption falls away — the space becomes part of the house and Part L thermal standards apply. This applies to your Lewisham address specifically. Lewisham Council is the decision-maker.
For planning, none — both are rear extensions assessed against the same Class A limits by Lewisham Council. The difference is in building control: an orangery's solid perimeter and flat roof with a lantern usually means it fails the glazing test for exemption, so it is fully regulated. That is why an orangery costs more to build but is comfortable in January.
Usually yes at the rear, though permitted-development rights are narrower on designated land and an Article 4 direction can remove them entirely. The assessment turns on whether the addition is visible from the street and how it meets the original rear elevation. A restrained orangery in matching brick with a lantern is consistently easier to get through than a proprietary glazed conservatory. This applies to your Lewisham address specifically. Lewisham Council is the decision-maker.
A fully glazed roof will, unless it is specified for it. That is the practical reason most of our clients end up building an orangery instead: a solid insulated roof perimeter with a lantern gives daylight without the greenhouse effect, and keeps the space usable across the year. We raise it at design stage because it is much cheaper to solve on paper than after the build. This applies to your Lewisham address specifically. Lewisham Council is the decision-maker.
If you excavate foundations within 3 metres of a neighbouring structure and deeper than its foundations, or build on the boundary itself, the Party Wall etc. Act 1996 applies and notice must be served. That is separate from Lewisham Council's planning decision. We flag it at design stage so the notice period does not delay the start on site.
We quote each Lewisham orangery or conservatory individually, because the structure and the roof form change the work considerably, and send a fixed, no-obligation quote within one working day. It covers the full drawing pack with free revisions until Lewisham Council approves. Call 020 7864 7245 to start.
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Same fixed quotes, same fast drawings — wherever your project is.