1Introduction

Extensions (single storey)


An extension or addition to your house is considered to be permitted development, not requiring an application for planning permission, provided certain limits and conditions are met.


This guide offers a visual walk-through of those limits and conditions.


For information about extensions of more than one storey, see our mini guide on two-storey extensions. For detailed information about single storey extensions, visit our common projects page.


Download: You can also download a PDF summary of this guide


Important note: The permitted development allowances described here apply to houses, not flats, maisonettes or other buildings. You should check with your Local Planning Authority whether permitted development rights apply – they may have been removed by what are known as Article 4 directions. Other consents may be required if your house is listed or on Designated land (Article 2(3) refers).


When planning work you should read all the advice on the Planning Portal under ‘Your responsibilities – Other considerations before you start work’.

As well as other important information you will find guidance here on the permitted development regime.


Wales: This guidance relates to the planning regime for England. Policy in Wales may differ. Contact your local planning authority for further information.


Disclaimer: Users should note that this is an introductory guide and is not a definitive source of legal information.


Read the full disclaimer.