‘Retaining the Heat inside your home’ has been designed to help and guide you to upgrade the energy performance of your home. It is here to help you have a good understanding of how to ensure your homes upgrades are done properly.

Energy Retrofit

Energy retrofitting of a home is about upgrading and renovating your home so that it will hold the heat in during winter and keep it cool during summer. This means you would need to add insulation, stop air leakages and much more.

Why should we retrofit?

Retrofitting your home impacts the environment less than producing new energy supplies to heating your home. Our homes use about 40% of energy to heat and cool. Most of this energy still comes from non-renewable resources such as oil and gas.
Our homes should always be comfortable and healthy. An air sealed, well insulated and ventilated home makes it very comfortable. It is also very quiet (no mechanical systems running to heat or cool it) and there is less pollen and is less dusty.
Your home will be more durable. When you retrofit your home, you also improve the moisture control. Resulting in a home that is in better shape and will last longer if done correctly.
Retrofitting your home will save you money in the form of lower energy bills.
When we consume less energy, we create fewer greenhouse gas emissions. Furthermore, we use fewer new resources when retrofitting than building a new home.

Retrofitting Opportunities

What will your strategy be? First you need to determine what condition your home is in. What needs to be done to improve its performance.
Check for moisture damage, structural damage, maintenance and items to fix. Find out the level of insulation, condition of insulation, air leakages and the age of the mechanical systems.
Although every house is different and unique here are some typical retrofitting opportunities:
  • Most homes would benefit highly from air leakage controls, moisture control and ventilation to reduce condensation.
  • Add extra insulation to your roof space.
  • Insulate your external walls
This series has been divided into 7 areas.
  • Understanding how your home works
  • Materials
  • Controlling Air Leaks
  • Roof spaces
  • Insulating walls
  • Windows and doors
  • How to operate your home

Understanding how your home works

To ensure that your home will meet your final expectations and that it should not cause you new issues you need to understand your home and how it works. This will explain how building science principles will help you control the heat flow through your home, air and moisture and why all these factors should be considered together.


This topic explains insulation, air barriers and vapour barriers. Choosing the right materials and installing them the right way will ensure that the finished job will live up to your expectations.

Controlling Air Leaks

Controlling air leaks is one of the most effective retrofit activity. It is essential. It is all about identifying and sealing all possible air leaks with caulking and stripping and by applying gaskets and tapes.


Even if the roof space is already insulated there may still be opportunity to improve the energy efficiency of the home through sealing. Air leaks into the roof space can account for a lot of heat loss.


Walls usually account for about 20% of heat loss in homes. There can be cracks in a wall that can allow uncontrolled air leaks in and out of the home.

Windows and Doors

Windows and doors usually account for about 25% of heat losses in our homes. Reseal, upgrade, or replace your wall openings.

Operating your home

Like any machine your home will work only as efficiently as you operate and maintain it. Operating it efficiently will maximise your retrofitting efforts and will actually improve your homes heating, cooling and ventilation efforts, performance and durability.

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