Blog > Category > Posted: 2022-Jun-28, Updated: 2023-May-04

Energy Star product specification comparisons

When making decisions on who to buy your windows from, the comparative information is easy to find. However, it can be a little overwhelming to decipher.

If window energy efficiency is important to you, then your best resource is the Natural Resources Canada, Energy Star Program. Visit their website for up-to-date information on Energy Star approved window products and specific product results that can be used for comparison.

Although there are almost 100,000 window models on the list, you can search specific manufacturers and window models to find efficiency rating data.

Even though all the technical information you could need is readily available, the specifications can be confusing and to make matters worse alternative rating units are sometimes used making it even more difficult to interpret the results.

Using the available product specifications spreadsheet we created a sample comparison sheet of some, but not all local products that are available in the Ottawa area. We chose single-casement windows for our example.

Our local sampling

For the sake of clarity and understanding, our trimmed-down example was created from the 2017 Canadian Energy Star Most efficient window supplier list which was downloaded from the Natural Resources Canada website:

1. We filtered out:

  • Many of the manufacturers that really don’t market themselves in the Ottawa area
  • Non-vinyl single casement windows
  • Windows that did not meet zone 1, 2 & 3 ratings
  • Excluded infill. Air Leakage L/s*m2 & Exfil. Air Leakage L/s*m2

2. Sorted the spreadsheet for the most efficient products/brands:

  • Energy rating
  • Solar heat gain
  • U-factor (Btu/h-ft2 F) & U-factor (W/m2 K)
  • Visible transmittance (VT)

3. Added green for the top 2 performers for each rating

The results

Filtering produced the best rankings for each manufacturer from the manufacturer’s list. The spreadsheet indicates the best ratings for each product shown.

Create and edit your own list


When it comes to window replacement, finding the right balance between energy efficiency, quality, and affordability can seem like a daunting task. But don't worry - by doing your homework, you can make a smart and informed purchase that will save you money and enhance the comfort of your home.

One key factor to consider when comparing different window products is their energy ratings. Most reputable window replacement companies will include this information in their quotes, but if they don't, be sure to ask for it. However, it's important to compare apples to apples and be aware that with so many variations of window products out there, it's easy to misread the specifications. Double-check your results to ensure you're making an accurate comparison.

By choosing the most energy-efficient windows, you can save money on your energy bills over time and enjoy a more comfortable home environment. Don't settle for subpar windows - with the right information and careful consideration, you can find the perfect windows to meet your needs and budget. So, take the time to do your research and make a wise investment in your home's future.


When shopping for products, it's important to do your research and compare different options to make an informed decision. This holds true when it comes to home improvements, such as purchasing new windows or doors. While it's easy to get swayed by brand names or sales pitches, it's important to look beyond those factors and focus on the specifications and model numbers provided by the companies you are considering.

In this post, we're not showing bias towards any particular brand, but rather providing sample findings to demonstrate the importance of looking at the specifics. So, don't just rely on the brand name or the sales pitch - take a closer look at the model numbers and specifications to determine which products best meet your needs and requirements. With the right information and careful consideration, you can make a smart and informed purchase decision that will bring long-term satisfaction and value to your home.

Related topics

What are window ratings?

CDN Energy Star Climate Zones

What is an R-value?

What are Energy Star energy ratings?

What is a U-factor?

What is the Solar Heat Gain Coefficient?

Infographic - Making windows energy-efficient

Infographic - ENERGY STAR labels & specifications

Infographic - What’s to know about Window Glass

Need more information?

Upgrade to energy-efficient windows today and save on your energy bills while reducing your carbon footprint! Contact us at Bayview Windows to explore our range of Energy Star rated windows and take the first step towards a more sustainable and cost-effective home.

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