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Household sustainability and energy efficiency improvements

If you are having an extension or other external alteration works carried out to your home, why not consider opportunities to improve its overall sustainability? 

This information provides guidance on the numerous sustainability improvement measures that can be applied when building an extension or carrying out other alterations to your home. 

You can also view and download a PDF copy of this guidance to save to your device for future use.

A householders guide to sustainability and energy efficiency improvements

Energy and water efficiency measures 

Triple glazed windows

Consider going beyond minimum Building Regulations requirements and installing triple glazed windows. 

Passive daylight

This refers to the installation of large windows in roofs such as skylights. These installations enable more natural light and heat to enter your home, saving energy from a reduced need for artificial lighting and heating. The level of passive heating and lighting can be managed by installing windows with blinds incorporated within the design.

Reclaimed or recycled materials

The use of reclaimed or recycled materials will reduce the environmental impact, could also save you money and result in the extension harmonising with the existing home.

Soft landscaping, e.g. tree planting and green roofs 

Tree planting can provide shade in summer and increase biodiversity in your garden. Green roofs can also increase biodiversity, reduce surface water run-off and act as a form of insulation. 

Dual flush WCs, lower flow taps and water efficient shower heads 

If you are installing a new bathroom consider choosing fixtures that reduce water usage. A water efficient shower head can also save gas for water heating. 

Rainwater harvesting

Rainwater harvesting can be as simple as a water butt to collect rainwater to use for watering the garden and washing the car. 

Highly efficient lighting schemes

LEDs are the most efficient light bulb on the market. 

Renewable energy

Instead of buying energy from suppliers you could install renewable technologies to generate your own energy. There are a variety of renewable energy technologies available, all with different requirements so it is important that you research the most suitable technology for your home. A large part of the cost of installing solar panels is the cost of scaffolding, if you are paying for scaffolding as part of your extension you may want to explore the potential and suitability for solar panels. 

Highly efficient new boiler

Extending the size of your home often requires improvements to your heating system and installation of new radiators. A more powerful boiler may be required so consider upgrading to a more efficient boiler. 


Your extension should be insulated to the standards stipulated by Building Regulations, but the rest of your home can also be insulated. If your home has cavity walls a layer of insulation can be blown into the cavity. If you have solid walls applying external insulation at the same time as your extension will ensure the exterior finish to the original building matches the extension. 


If you are having a kitchen installed, consider choosing the most energy efficient appliances. 

Draught proofing of windows and doors 

Draught proofing is one of the simplest and cheapest ways to save money and energy. To draught proof your home block up unwanted gaps that let cold air in and warm air out.

Further information

For more information about energy efficiency, and home upgrades or extensions, email 

For more information about planning, email 

Listed Buildings and buildings within conservation areas need extra thought about how to improve their energy performance without compromising their special interest. Contact Planning Services, to discuss a bespoke solution.


Page last reviewed: 15 September 2020


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