Do You Need Planning Permission for a Conservatory?
Many conservatories can be built without a full planning application in England, but only when the project meets the relevant permitted development limits and conditions.
A conservatory is treated in the same way as an extension for planning purposes, so its size, position, height, previous additions to the property and any local planning restrictions can all affect whether permission is required.
Planning Permission May Depend On
- The size and height of the conservatory
- How far it extends from the original house
- Its position in relation to boundaries and highways
- Previous extensions and other buildings
- Whether permitted development rights apply
- Whether the property is listed or in a protected area
Can You Build a Conservatory Without Planning Permission?
Often, yes. Conservatories can fall within permitted development rights in England when all of the relevant conditions and limitations are satisfied.
However, permitted development is not automatic. The rules depend on the property, the position and dimensions of the proposed conservatory, previous extensions and whether any planning restrictions apply to the house.
What Are the Main Planning Rules for a Conservatory?
Because a conservatory is treated as an extension, the normal householder permitted development rules apply rather than a separate set of conservatory rules.
Overall Site Coverage
Extensions and other buildings must not result in more than half of the land around the original house being covered by additions or other buildings.
Position of the Extension
An extension generally cannot be built forward of the principal elevation of the original house, or forward of a side elevation where that elevation fronts a highway, under normal permitted development rights.
Height
A single-storey rear extension must not normally exceed four metres in height. Where an extension is within two metres of a boundary, additional limits apply to the height of its eaves.
Previous Extensions Matter
Existing extensions can affect what can still be built under permitted development. The rules assess the proposed work together with relevant previous enlargements to the original house.
How Far Can a Conservatory Extend Without Planning Permission?
For a typical single-storey rear extension under standard permitted development rights, different limits apply depending on the type of house.
Up to 4 Metres
A single-storey rear extension can normally extend up to four metres beyond the rear wall of the original detached house under the standard permitted development limit.
Up to 3 Metres
For other houses, including semi-detached and terraced homes, the standard permitted development limit is normally three metres beyond the rear wall of the original house.
What About a Larger Rear Conservatory?
In some cases, larger single-storey rear extensions can use the prior approval process rather than a normal householder planning application.
Subject to the applicable conditions, the larger-home-extension route can allow up to eight metres beyond the original rear wall for a detached house or six metres for other houses. The local planning authority must be notified and a neighbour consultation process applies.
This route is not available in every location or circumstance, so it should be checked with the local planning authority before work begins.
What About a Conservatory at the Side of a House?
Different permitted development restrictions apply when a conservatory extends beyond a side wall of the original house.
- It must normally be single storey.
- It must not normally exceed four metres in height.
- Its width must not normally exceed half the width of the original house.
- Additional restrictions apply on designated land such as conservation areas.
When Might a Conservatory Need Planning Permission?
A planning application may be required where the proposed conservatory falls outside permitted development rights or where those rights do not apply.
The Design Exceeds the Limits
Permission may be needed if the conservatory is too large, too high, projects too far from the original house or is positioned somewhere not covered by permitted development.
Permitted Development Rights Are Restricted
Some properties have had permitted development rights removed through planning conditions or an Article 4 Direction.
The Property Is a Flat or Maisonette
Householder permitted development rights for extensions do not apply to flats and maisonettes in the same way that they apply to houses.
The Property Is in a Protected Area
Conservation areas and other designated land can have tighter restrictions, particularly for side extensions and certain external alterations.
Can You Add a Conservatory to a Listed Building?
Listed buildings are subject to additional controls. A conservatory or other extension that affects the building's special architectural or historic character will require Listed Building Consent.
Planning Permission and Building Regulations Are Not the Same
Planning permission primarily considers whether development is acceptable in planning terms. Building Regulations deal with technical standards such as construction, structural work, glazing, electrical safety and energy performance.
Can the Development Be Built?
Planning rules consider matters such as the size and location of the extension, its relationship with the existing property and whether permitted development rights apply.
How Is the Work Constructed?
Building Regulations cover technical construction requirements. Some conservatories can qualify for an exemption, but only when the relevant conditions are met.
Are Conservatories Exempt from Building Regulations?
A conservatory can normally be exempt from Building Regulations where it meets specific conditions.
- It is built at ground level.
- Its internal floor area is less than 30 square metres.
- It remains separated from the house by external-quality walls, doors or windows.
- Any heating system is independent and has separate temperature and on/off controls.
- Glazing and fixed electrical installations still meet the applicable safety requirements.
Removing the Doors Between the House and Conservatory?
If the project involves creating or enlarging a structural opening between the conservatory and the existing house, Building Regulations approval will normally be required even where the conservatory itself would otherwise qualify as exempt.
How Can You Check Whether Your Conservatory Is Permitted Development?
Because every property and proposed design is different, it is sensible to check the position before starting work.
Your local planning authority can advise whether local restrictions apply. Where you want formal confirmation that a proposed conservatory is lawful under permitted development rights, it is also possible to apply for a Lawful Development Certificate.
This guide applies to homes in England. Planning systems and permitted development rules differ elsewhere in the UK.
Conservatory Planning Permission FAQs
Do all conservatories need planning permission?
No. Many conservatories on houses can fall within permitted development rights when all of the relevant size, height, position and other conditions are satisfied.
Is a conservatory treated differently from an extension?
No. For planning purposes in England, a conservatory is generally treated in the same way as another extension to the house.
Do previous extensions affect permitted development?
Yes. Previous enlargements to the original house can affect how much further development is permitted, so the proposed conservatory should not be assessed in isolation.
Can I build a larger rear conservatory under permitted development?
Some larger single-storey rear extensions may use the prior approval process, subject to the applicable limits, conditions and neighbour consultation.
Does a conservatory need Building Regulations approval?
Some conservatories can qualify for an exemption, but only when specific conditions are met. Structural alterations to the existing house can still require Building Regulations approval.
Do listed buildings have different rules?
Yes. Listed Building Consent may be required for an extension that affects the building's special architectural or historic character, and planning permission may also be required separately.
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