Conservatory Planning Permission: Overview

Adding a conservatory to your home can be a great investment. In a short space of time you can transform a wasted area of garden into a useful, beautiful room for you and your family to enjoy. And at the same time, you can add substantial value to your home, as well as acres of curb appeal, making it easier and more profitable to sell down the line.

But before you can start building your new conservatory, you need to be sure that everything is above board. Planning authorities can be notoriously harsh, even forcing the demolition of homes of epic proportions when they break the rules, so asking you to take down an illegal conservatory is not going to cause them any sleepless nights! The strategy here is, stay within the law to the absolute letter, then you won’t have any trouble later on. Here’s what you need to know.

What is planning permission?

Sometimes it’s easy to confuse planning permission and building regulations. It’s a good idea to have a general overview of both and how they relate to your conservatory if you’re planning a

Planning permission

Planning is concerned with the way our villages, towns and cities develop, and how the buildings in the locations look and work together. They care about the use of the land and the landscaping around our buildings, and the impact our development will have on the environment locally. Most of the aspects of your conservatory will not need to be considered in terms of planning, but some will.

Building regulations

Building regulations relate to the construction and design of buildings, and are concerned mainly with the safety of those buildings. They include requirements for the conservation of energy, and strive to make our homes safer, healthier and more future proof.

Understanding the difference in these two streams of legislation and control can help you speak to the right people at your local council when looking for advice. In general, a standard conservatory should be exempted from both streams of control, but it does require some effort on your part.

Making sure your conservatory is a permitted development

Usually, conservatories are classed as what is known as ‘permitted development’, which means you do not have to go through the planning process at all. However, there are some rules you need to abide by to ensure your building is permitted under planning guidelines.


No more than half of the land around your building should be covered by your conservatory.


The conservatory should not be forward of the principle or side elevation of the original house and facing the road.


No part of the conservatory should be higher than the highest part of your roof. The maximum height should not exceed 4m.


The conservatory should not extend beyond the rear wall of the house by more than 6m in an attached house or by 8m in a detached house.

Side located

Side conservatories should be no more than 4m tall and have a width of no more than half the original house.

If you live on what is known as ‘designated land’, which includes Sites of Special Scientific Interest, Areas of Outstanding Natural Beauty and National Parks, additional requirements may come into play. There is a useful guide to keeping your conservatory a permitted development here, but you should talk through your plans with your local planning department to ensure you are keeping within the rules.

If you are planning a particularly large conservatory (extending beyond the original house wall for more than 3m in an attached house and 4m in a detached house) you will need to go through the Neighbour Consultation Scheme. There is a mini guide on the Planning Portal which covers all aspects of conservatory planning, including building regulations and case studies.

This guidance is based on the latest iteration of the permitted development scheme at time of publication, which runs from 30th May 2013 to 30th May 2019.