Windows are one of the biggest points of energy loss for a home and it is essential that they be adequately upgraded and maintained to keep your energy bill low. In fact walls, can account for about 20% of heat loss in homes.  They perform a variety of functions in a home. While they do facilitate natural light in a home, they can be a significant source of energy loss. This can be through radiation through glazing, air leakage around the frame, or conduction.  Accordingly, it is essential to understand the window elements and its properties that affect its performance. Read on The Factors That Affect Your Window Choice.

See the Types of Window Retrofits to explore window solutions that work with your energy goals and budget.


You can save

on your heating and cooling costs just by replacing single pane windows with double pane windows


Find the right type of retrofit that fits your budget, performance and energy needs.

A minor retrofit is small changes that you can make to your home that are low in cost and yet make a difference in energy consumption such as sealing cracks around the window.

A major retrofit takes on a more holistic approach that is higher in cost such as replacing window glazing and doors.

A deep retrofit is more extensive and costly such as rearranging windows in your home.


Replacing all your windows with Energy Star certified windows can save you an average of 45% on your energy bill


Factors That Affect Your Window Choice

Stacks of Windows

There are several factors that impact the type of window retrofit you need, which are outlined below:

  • House Age/Condition of Home: An older home might have damaged window sills or frames which can impact the integrity of the window. In this case, it is important that a full frame replacement is considered, resulting in a deep retrofit. Alternately, older window sills may have more aesthetic 

  • Exterior material: Different facades may require different types of window retrofits. 

  • Existing Condition of Frame and Surrounding Area: An older frame or any cracks or gaps around the window sill indicate a deeper retrofit is necessary.

  • Personal Requirements: Based on your preferences and tastes, as well as the financial and time commitment you are willing to make, you may decide to opt for a different level of window retrofit. 

It is not just important to choose the right window but also ensure it is properly installed. Always use a certified building specialist or contractor for this to minimize any chances of leakage that will drive up your energy bills.

Various window inserts and frames.

Image obtained from: Wix Images

Energy Rating System

In Canada, the energy performance of a window is measured through the Energy Rating (ER) system. The ER rating takes several of the factors listed above into consideration including U-Factor, SHGC and leakage. A higher ER number on a window indicates more energy efficiency. Several accredited associations in Canada use this standard and you should always check carefully for a certification label on your product.


Homeowners who install Energy Star windows save an average of 12% on their utility bill throughout the year


1. Canada NR. Government of Canada [Internet]. Natural Resources Canada. / Gouvernement du Canada; 201. Available from:

2. Natural Resources Canada. (2020, September 18). Government of Canada - Ratings and Certification. Available from: