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Do You Need Planning Permission for a Conservatory? UK 2026 Guide

Bhavesh Ramburn

Do you need planning permission for a conservatory?

Short answer: A conservatory is usually Permitted Development in England and does not need planning permission, provided it meets the Class E test under the Town and Country Planning (General Permitted Development) (England) Order 2015 (the GPDO) and satisfies the height, footprint, and curtilage limits. However, several specific scenarios push a conservatory outside Permitted Development, requiring a planning application.

Whether planning permission is required depends on four factors:

  1. The location of the conservatory (front, side, rear of the dwelling).
  2. The size of the conservatory (height, footprint, area relative to the curtilage).
  3. The relationship to the principal elevation of the original house.
  4. Local restrictions (Conservation Area, Area of Outstanding Natural Beauty / National Landscape, Article 4 Direction, listed building).

For the broader context, see our Permitted Development Rights in 2026 guide and our householder planning permission guide.

The Class E test — when a conservatory is Permitted Development

A conservatory is generally Permitted Development under Class E, Schedule 2 of the GPDO 2015, which covers “buildings, enclosures, pools and other structures required for a purpose incidental to the enjoyment of the dwelling house.” This Class also covers garden sheds, summerhouses, car ports, and similar outbuildings.

Class E applies to a conservatory provided all of the following limits are satisfied:

  • The conservatory is within the curtilage of the dwelling house.
  • The conservatory, together with any other buildings and enclosures within the curtilage (excluding the original dwelling), does not cover more than 50% of the curtilage of the original dwelling.
  • The conservatory is not forward of the principal elevation of the original dwelling.
  • The conservatory is not more than 4 metres in height if it has a ridged roof, or not more than 3 metres in height if it has any other roof.
  • The conservatory is not more than 2.5 metres in height if any part is within 2 metres of a boundary of the curtilage.
  • The conservatory is for a purpose incidental to the enjoyment of the dwelling house (e.g. a sun room for private enjoyment, not a commercial venue).
  • The conservatory is not used in connection with a commercial business.

Where all of these limits are satisfied, the conservatory is Permitted Development and no planning application is required.

For the broader Class E limits, see our Building Regulations for outbuildings over 30 m² guide.

Front-of-house restrictions

A conservatory forward of the principal elevation is not Permitted Development under Class E. This means:

  • A conservatory in the front garden (between the house and the road) is generally not Permitted Development and requires planning permission.
  • A conservatory to the side of the house may be Permitted Development if it is behind the principal elevation (i.e. set back from the front wall of the house).
  • A conservatory to the rear of the house is generally Permitted Development provided the height limits are satisfied.

The “principal elevation” is the elevation of the original dwelling that faces the road. Where the road is at the front of the house, the principal elevation is the front. Where the road is at the side or rear (a common arrangement on corner plots), the principal elevation is the road-facing side.

For most semi-detached and terraced houses, the front garden is forward of the principal elevation, so a front-of-house conservatory is rarely Permitted Development. Most conservatories are installed to the rear of the house, which is generally Permitted Development.

Where a front-of-house conservatory is proposed, planning permission is required.

Height limits for a conservatory

The GPDO 2015 height limits for a Class E structure are:

  • Ridged (pitched) roof: maximum 4 metres total height.
  • Any other roof (flat, mono-pitched, hipped, pyramidal): maximum 3 metres total height.
  • Within 2 metres of a boundary: maximum 2.5 metres total height (regardless of roof type).

The height is measured from the ground level at the boundary to the highest point of the structure. For a conservatory with a pitched glass roof, the ridge (top) must be no more than 4 metres; for any other shape, the highest point must be no more than 3 metres. Where any part of the conservatory is within 2 metres of a boundary, the 2.5-metre limit applies to that part.

A two-storey conservatory is rarely Permitted Development. Most conservatories are single-storey.

Curtilage and the 50% rule

A conservatory, together with any other Class E structures and any extensions to the original dwelling, must not cover more than 50% of the curtilage of the original dwelling. The “curtilage” is the enclosed area of land immediately surrounding the dwelling, typically including the front, rear, and side gardens.

The 50% test is the most common reason a conservatory requires planning permission in suburban areas where the garden is small. For example, on a terraced house with a 60 m² rear garden, the cumulative area of all extensions, sheds, and the conservatory must not exceed 30 m².

Where a conservatory would push the cumulative area over 50%, planning permission is required.

For a worked example of how the 50% rule applies to a rear garden, see our Building Regulations for outbuildings over 30 m² guide.

Conservation Areas and Permitted Development rights

In a Conservation Area, Permitted Development rights are restricted in two important ways for conservatories:

  • Class E prior approval. Under a 2024 update to the GPDO, Class E now requires prior approval for any new building, including a conservatory, where the LPA must consider the impact on the Conservation Area.
  • Article 4 Directions. Many Conservation Areas have Article 4 Directions in force that withdraw Class E Permitted Development rights entirely. Where an Article 4 Direction is in force, planning permission is required for any conservatory, regardless of size or location.

For more on Conservation Areas and Article 4 Directions, see our Permitted Development Rights in 2026 guide.

National Landscapes (formerly AONBs) and Permitted Development rights

In an Area of Outstanding Natural Beauty (AONB) — renamed National Landscape in England by the Levelling Up and Regeneration Act 2023 — Permitted Development rights are still in force, but the LPA is required to give greater weight to the conservation of landscape beauty. This can effectively limit the size and design of any conservatory in a National Landscape.

In a National Park (e.g. the Lake District, Peak District, Snowdonia / Eryri, Dartmoor, Exmoor, the Yorkshire Dales, the North York Moors), planning permission is always required for Class E structures because the National Park Authority is the LPA and applies its own planning policies.

For more on the National Landscape and National Park regimes, see our Permitted Development Rights in 2026 guide.

Listed Buildings and Permitted Development rights

For a listed building, Permitted Development rights do not apply. Planning permission and Listed Building Consent are both required for any conservatory, even a small one. The Listed Building Consent application is decided separately from the planning application and is concerned with the impact on the special interest of the building.

For more on listed building consent, see our Permitted Development Rights in 2026 guide.

Building Regulations for a conservatory

A conservatory has a narrow Building Regulations exemption under the original Building Regulations regime, but this is narrower than many homeowners realise:

  • Under 15 m² with thermal separation. A conservatory of under 15 m² that is separated from the dwelling by walls, doors, or windows that meet Part L thermal standards, and has no heating, is exempt from Part L (Conservation of fuel and power).
  • Over 15 m² or no thermal separation. A conservatory that exceeds 15 m² or shares the dwelling’s heating system is not exempt and requires a Building Regulations application.

Other Parts of the Building Regulations still apply, including:

  • Part A (Structure) for the foundations and frame.
  • Part B (Fire safety) for fire separation and means of escape.
  • Part K (Protection from falling) for any glazed roof that could be walked on.
  • Part N (Condensation) for the prevention of harmful condensation, which is a common problem in conservatories.
  • Part P (Electrical safety) for any electrical work.

For the broader Building Regulations context, see our Building Regulations UK guide and our Building Regulations for outbuildings over 30 m² guide.

What if planning permission IS required?

Where a conservatory is outside Permitted Development, planning permission is required. The process is:

  1. Pre-application advice (optional). Most LPAs offer a paid pre-application advice service.
  2. Application submission. Submit the planning application via the Planning Portal, with the required drawings, the application form, and the application fee.
  3. Validation. The LPA validates the application.
  4. Public consultation. The LPA advertises the application by site notice and neighbour letter. The public has 21 days to comment.
  5. Determination. The planning officer determines the application. The statutory determination period is 8 weeks for householder applications.
  6. Decision. The LPA issues a decision notice.
  7. Appeal. If refused, an appeal can be made to the Planning Inspectorate in Bristol.

For the broader planning-permission process, see our householder planning permission guide and our UK Planning Appeals guide.

How to check if your conservatory is Permitted Development

There are several ways to check whether your conservatory is Permitted Development:

  • DIY PD check. Walk through the Class E test in the GPDO 2015 and the Schedule 2 limits.
  • Planning Portal PD checker. The Planning Portal hosts an interactive Permitted Development checker that walks through the test step by step.
  • Pre-application enquiry to your LPA. Most LPAs offer a paid pre-application advice service.
  • Independent planning consultant. A chartered planning consultant registered with the RTPI can review the proposal and confirm whether planning permission is required.
  • Certificate of Lawfulness application. Submit a Lawful Development Certificate (LDC) application to your LPA. The LPA will issue a certificate confirming whether the conservatory is Permitted Development. The fee is typically half the full planning application fee.

The LDC route is the most secure option where the position is unclear, and is often used by homeowners to confirm the position before starting work.

For more on Lawful Development Certificates, see our Permitted Development Rights in 2026 guide.

Common scenarios and whether planning permission is required

Scenario Planning permission required?
3 × 4 m single-storey rear conservatory, semi-detached house Generally no — Permitted Development under Class E
5 × 4 m rear conservatory Generally no — Permitted Development under Class E
6 × 4 m rear conservatory on a 50 m² garden Possibly — depends on cumulative 50% curtilage test
Front conservatory Yes — front extensions are not Permitted Development
Two-storey conservatory Yes — exceeds the 4 m height limit
Conservatory within 2 m of boundary exceeding 2.5 m height Yes — exceeds the 2.5 m near-boundary limit
Conservatory in a Conservation Area with an Article 4 Direction Yes — Article 4 removes PD rights
Conservatory to a listed building Yes — Listed Building Consent and Planning Permission required
Conservatory in a National Park Yes — National Park Authority is the LPA
Conservatory with shared heating Building Regulations apply; planning PD position unchanged

Next steps and resources

Editorial note. This article is for guidance only and does not constitute regulated advice. The GPDO 2015 is the primary source of Permitted Development rights for conservatories and is regularly updated. Always check the current version of the GPDO before relying on a Permitted Development position, and consider obtaining a Lawful Development Certificate to confirm the position. For project-specific questions, consult a chartered planning professional registered with the Royal Town Planning Institute (RTPI).