Orangery and conservatory drawings for Brentwood homes — checked against the Class A rear limits and the 30m² building-regulations exemption, drawn to Brentwood Borough Council's guidance and revised free until your decision.
Brentwood Borough Council granted 84% of the householder planning decisions it made in its latest published year — 3 points below the 87% England-wide householder average. Roughly 89% of the borough is Metropolitan Green Belt, so most growth is steered to allocated sites and village and countryside proposals face strict very-special-circumstances tests, which is where a policy-literate drawing pack earns its keep. Its dominant Georgian (1714–1837), Victorian (1837–1901), Edwardian (1901–1910), interwar (1918–1939) and postwar (1945–1970) 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. Brentwood carries at least one Article 4 direction, and conservation areas including Brentwood Town Centre, Hutton Village and Ingatestone Village Centre remove those rights outright, so we confirm your exact address before a line is drawn. A validated householder application in Brentwood is determined against an 8-week statutory target.
Brentwood (the town centre with Victorian and Edwardian terraces and a High Street conservation area), Shenfield (affluent interwar and postwar semis and detached houses at the Elizabeth line commuter hub), Hutton (interwar-to-modern suburban housing, with the prestige detached enclave of Hutton Mount), Ingatestone (a historic village with a Georgian and timber-framed core and a station-area conservation zone), Blackmore (a green-belt village of timber-framed and period cottages around the green) and Herongate (a small green-belt village of rural detached and period housing) — these are the Brentwood pockets our drawings cover most. Heritage designations here include Brentwood Town Centre, Hutton Village, Ingatestone Village Centre, Blackmore, South Weald and Herongate. Brentwood Borough Council weighs each proposal against the Brentwood Local Plan 2016–2033 (adopted March 2022), where woodland Article 4 directions remove permitted-development rights over designated woodlands to protect habitat. Converted flats appear around Brentwood town centre and Shenfield station, and none of them hold householder permitted-development rights.. On roofs the borough is hipped roofs on the interwar and postwar suburban semis and steep tiled and gabled roofs on the timber-framed village cottages, over Victorian and Edwardian and twentieth-century suburban housing around Brentwood and Shenfield, the interwar detached enclave of Hutton Mount, timber-framed and Georgian cores in the historic villages of Ingatestone and Blackmore and rural detached and period housing across the green-belt villages.
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 Brentwood Local Plan 2016–2033 (adopted March 2022). Brentwood is largely Victorian and Edwardian and twentieth-century suburban housing around Brentwood and Shenfield, the interwar detached enclave of Hutton Mount, timber-framed and Georgian cores in the historic villages of Ingatestone and Blackmore and rural detached and period housing across the green-belt villages, 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 Brentwood Town Centre and Hutton Village, rear glazing is assessed on visibility from the street and on the effect on the rear elevation's character. Brentwood's Article 4 directions are used chiefly to withdraw permitted-development rights over designated woodlands so that works there require planning permission, and the borough's thirteen conservation areas such as Hutton Village and Ingatestone add further character controls.
Many conservatories are permitted development. You will need an application to Brentwood Borough 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 Brentwood Borough Council's real householder decision record, drawn from official planning statistics and refreshed as new data lands. Brentwood grants a little below the national average of applications, with heavy Green Belt coverage and conservation-village character the pressures that shape most schemes. Glazed rear additions are judged on depth, eaves height and how the glazing meets the existing elevation.
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 Brentwood, Shenfield and Hutton, 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 and edwardian and twentieth-century suburban housing around brentwood and shenfield, 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.
Roughly 89% of the borough is Metropolitan Green Belt, so most growth is steered to allocated sites and village and countryside proposals face strict very-special-circumstances tests. 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 Brentwood. A few of the areas where they come up most often:
Orangery and conservatory drawings for Brentwood — the town centre with Victorian and Edwardian terraces and a High Street conservation area — checked against the Class A limits and drawn to Brentwood Borough Council's guidance.
Orangery and conservatory drawings for Shenfield — affluent interwar and postwar semis and detached houses at the Elizabeth line commuter hub — checked against the Class A limits and drawn to Brentwood Borough Council's guidance.
Orangery and conservatory drawings for Hutton — interwar-to-modern suburban housing, with the prestige detached enclave of Hutton Mount — checked against the Class A limits and drawn to Brentwood Borough Council's guidance.
Orangery and conservatory drawings for Ingatestone — a historic village with a Georgian and timber-framed core and a station-area conservation zone — checked against the Class A limits and drawn to Brentwood Borough Council's guidance.
Orangery and conservatory drawings for Blackmore — a green-belt village of timber-framed and period cottages around the green — checked against the Class A limits and drawn to Brentwood Borough Council's guidance.
Orangery and conservatory drawings for Herongate — a small green-belt village of rural detached and period housing — checked against the Class A limits and drawn to Brentwood Borough 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 Brentwood postcode and house type. We confirm the Class A limits that apply, check designation status, and score your odds against live Brentwood Borough 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 Brentwood Borough 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 Brentwood you will need an application to Brentwood Borough Council beyond those limits, and on designated land such as Brentwood Town Centre and Hutton Village.
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 Brentwood address specifically. Brentwood Borough Council is the decision-maker.
For planning, none — both are rear extensions assessed against the same Class A limits by Brentwood Borough 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 Brentwood address specifically. Brentwood Borough 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 Brentwood address specifically. Brentwood Borough 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 Brentwood Borough Council's planning decision. We flag it at design stage so the notice period does not delay the start on site.
We quote each Brentwood 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 Brentwood Borough Council approves. 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.