Holland and Green Architects

Oxford + SW London

PDR - Extensions

Permitted Development Rights now allow home owners to add single storey and often two storey extensions to their homes without the need for Planning Permission so long as they stay within the guidelines laid out by the legislation.

The nature of Permitted Development means that you are able to create visually impressive extensions that would most probably not be allowed with Planning Permission. For example there are no restrictions on the use of glass, so should you choose, you could create a cutting edge glass extension without fear of falling foul of the planning inspector.



     BEFORE                                                               AFTER

Key Permitted Development Restrictions on Extensions


• Extensions must not be higher than the eaves of the existing property.
• Total buildings must not cover over 50% of the total plot – excluding the existing dwellinghouse.
• Single storey extensions must be less than 4 meters high.
• Extension eaves height must be 3 meters or less if within 2 meters of the boundary.
• The extensions eaves must not be higher than the eaves of the existing house.

Rear Extensions:

Single Storey

• Terraced or Semi-detached houses can extend 3 meters from the existing property.
• Detached properties can extend 4 meters from the existing property.

Double Storey

• Double storey extensions can project 3 meters for all types of house.
• Double storey extensions must be a minimum of 7 meters from a boundary.

Side Extensions:

• Side extensions must be less than half of the width of the existing property.
• Two storey side extensions are not allowed under Permitted Development.
• Corner plots can hold additional restrictions.


The above details are a guide only and are not exhaustive. Every property is unique and your home could have restrictions on it’s permitted development rights. Holland and Green recommend all of our clients obtain a Certificate of Lawful Development before undertaking any building work. A Certificate of Lawful Development is a legally binding document from your local council confirming that the work you are undertaking falls within Permitted Development allowances.



No Matter where you live in the UK Holland and Green are able to establish your Permitted Development Rights and will be able to compile a bespoke Permitted Development Report on your home detailing exactly what your Permitted Development Rights are and showing you how much space you can add to your home.


Extensions Home Page


Holland and Green can take no responsibility for any works that are undertaken without our consultation.