If you are like most homeowners in Winnipeg looking for a window and door replacement, chances are there are companies literally knocking on your door offering their services. But how do you see through the clutter and find value in what’s out there?

Remember, the success of your window replacement depends on both, quality product and correct installation.

But since most vinyl windows on the market look nearly identical to the untrained eye, it may be outright confusing trying to discern a quality window from a poorly made one.

That’s what we will focus on in today’s article.

Be sure to check how windows from different Winnipeg companies compare:
Casement Windows In Winnipeg
Slider Windows in Winnipeg
Awning Windows in Winnipeg


Regardless of the window type, there are two main factors to consider when comparing and picking quality windows:

  1. The windows you get should be tested by, and adhere to CSA standards.
  2. For maximum comfort and efficiency, the windows you get should be rated by ENERGY STAR to be recognised as energy-efficient model and bring maximum value, comfort and qualify for government rebates available in Winnipeg.

Because both the Canadian Standards Association (CSA) and ENERGY STAR rely on similar criteria for evaluating windows, usually if a window is good enough to qualify for one standard, it also qualifies for the other. Very rarely will you see a window manufacturer that sells ENERGY STAR qualified windows, that don’t meet the CSA standard.

We will break it down further below, but this information is publicly available for you to see:
Check out ENERGY STAR rated window companies here
Find out which windows in Canada meet CSA standards

Understanding CSA standards for comparing windows

As a Canadian window consumer, the windows you purchase should adhere to the CSA – A440 standard. The Canadian Standards association has laid out specific guidelines for window performance in these categories:

  1. positive design pressure, where applicable;
  2. negative design pressure, where applicable;
  3. water penetration test pressure; and
  4. air infiltration and exfiltration level.
CSA labelling provides information about the performance of a window right on the product.
These are the maximum and minimum ratings for different types of windows.
Additional ratings that CSA considers when testing windows.
Other ratings that CSA considers when testing windows.

Sometimes you will see windows with ABC ratings. For example, a window that is rated A3, B6, C4 is more efficient and better performing than a window that is rated A3, B6, C2.

One way to recognize whether windows are CSA certified is that they have a CSA logo on the glazing and come with a CSA label that outlines the window’s performance metrics in the four categories mentioned above. But if you look at the picture below, you’ll see that the ratings provided on the label, aren’t the same as the ones used by CSA.

While the CSA-A440 is the minimum standard all windows installed in Canada should comply to, different windows have their own unique Energy Ratings (ER) based on several measurements of performance. Energy Ratings are a more simplified and harmonized way to understand and compare window performance.

Understanding ENERGY RATINGS when comparing windows

A window’s ER rating is calculated on three factors: solar heat gains, heat loss through frames, spacers and glass, and air leakage heat loss. ER ratings rank between 0-50, the higher the rating, the more efficient the window.

The ER number is a balance between heat loss ratings (U-Factor) and solar heat gains through the window (SHGC).

  • U-Factor is a measure of how much heat a window system loses. Note the use of the word system here. Traditionally window performance was often judged by the R-value of the materials used, but modern windows often use different materials with different R-values, so it is not accurate to measure these values in relation the window as a whole. The lower the U-Value, the less heat is lost through the whole window. Some of the best thermal windows on the market achieve a U-Value of 1 or slightly lower.
  • Solar Heat Gain Coefficient (SHGC) is a fraction of how much UV heat is allowed to pass through the glass into your home. SHGC can range from 0 to 1, but the higher the coefficient, the more heat your windows gain from the sun. SHGC also has a direct effect on the energy rating of a window. It only makes sense: a window that allows more heat in, is technically more efficient because it, in turn, requires less energy to keep the home warm.

However, the efficiency of modern vinyl windows is relatively high to a point where windows with higher SHGC ratings can actually overheat rooms even in the winter time. This is especially true for unshaded windows facing south or west, and in homes with high window to wall ratio.

Although it is meant only for comparison purposes, the ER number is still a good indicator of the effect windows will have on your annual heating costs. The lower the number, the more heat is lost and the harder the heating system has to work in colder weather.

As of January 2020, homeowners no longer have to consider a Climate zone when shopping for windows that are ENERGY STAR® certified in a particular area. A product in Canada is either ENERGY STAR® certified or not, with a single standard applied nationwide.

And to be considered efficient in Winnipeg, windows must have a minimum ER number of 34 and a maximum U-Factor of 1.40

Importance of correct window installation

One thing we briefly mentioned in this post is window installation. While “how” your windows will be installed may not be taken into consideration when comparing the quality of the actual product, you should know that correct installation accounts for half of the success of your window replacement. Even the best replacement windows can cause your home to lose heat if they are not installed properly. Consider window companies in Winnipeg that have good reviews about their installation services.

Find our more about how we price our windows and what our window purchasing process looks like.

Check out these window replacement articles:
Window Prices in Winnipeg: Plan For Your Replacement
Full Frame or Retrofit: Window Installation in Winnipeg
Best Window Companies in Winnipeg: 2015