Energy Star
CDN Climate Zone

Before we begin, here are some Energy Star Resources
for you to take a look at:

• Compare window performance by brand, type and energy efficiency
• Technology Primer
• Buy Energy Star to save money
• ENERGY STAR® rebates and incentives directory
• ENERGY STAR Technical Specifications - 2020 (NRC)

Be sure to select the ENERGY STAR Most Efficient (YEAR): checkbox to see the most efficient windows for the YEAR.

Window ENERGY STAR Ratings “Out with the old and in with the new!”

Our world is always advancing with innovative products and processes aimed at simplifying our lives. The Energy Star Window Standards in Canada are a prime example of this progress. Learn how these standards and their related Climate Zones have been streamlined for your convenience.

No more thinking required

The three separate Energy Star Climate Zones in Canada, which were in place from 2015 to 2019, have now been consolidated into a single zone. Starting January 1, 2020, the Energy Star window program, which encompasses standards for Canadian manufacturers, installers, and residential home builders, has been streamlined. Rest assured, this new single-zone system doesn’t mean that requirements have been reduced. In fact, for regions with milder temperatures, the standards have been elevated.

See the old Energy Star Climate Zones

How are ENERGY STAR ratings formalized?

n Canada, window energy performance is evaluated according to the Canadian Standards Association (CSA) A440.2 standard. Energy Star Certification, managed by Natural Resources Canada, assesses the energy efficiency of windows and doors using a variety of metrics.

Energy performance is rated using the following values:

1. The U-factor 
(The lower the number, the more efficient the product)

The U-factor is the rate of heat transfer from warm to cold areas in watts per square metre Kelvin (W/m2K) or in British thermal units per hour per square foot Fahrenheit (Btu/h x sq. ft. x °F).

2. Solar heat gain coefficient (SHGC) 
(The higher the number, the more solar heat the product gains)

A solar heat gain coefficient is a ratio showing the amount of the sun’s heat that can pass through the product.

3. The R-value 
(The higher the number, the more efficient the product)

The R-value is a value indicating the resistance to heat transfer in square feet per hour in degrees Fahrenheit per British thermal unit (sq. ft. x h x °F/Btu).

(The R-value is not part of the energy performance standards, but is often quoted by contractors and sales staff as a measure of performance.)

4. Visible transmittance (VT) 
(The higher the number, the more light can pass through)

Visible transmittance is the ratio of the amount of visible light that can pass through a product.

5. Centre-of-glass rating

The centre-of-glass rating an energy-efficiency value refers only to the glass portion of a window product and not as a whole.

6. The Energy Rating (ER) 
(The higher the number, the more efficient the product)

A value demonstrating the balance between U-factor, SHGC and air leakage. ER values can be presented in Imperial or Metric Units of measurement.

7. Air Leakage (AL) 
(The lower the AL, the less air will pass through cracks in the window assembly)

The air leakage value is a heat loss and gain that occurs by infiltration through cracks in the window assembly. It is indicated by an air leakage rating (AL) expressed as the equivalent cubic feet of air passing through a square foot of window area. This rating must be 0.30 or less to qualify for Energy Star Certification.

ENERGY STAR - Minimum qualification criteria for windows

Products that achieve ENERGY STAR certification are independently verified to save energy, reduce costs, and help protect the climate. To qualify for ENERGY STAR, a window or door must meet a specified minimum Energy Rating (ER) or a maximum U-Factor value.

ENERGY STAR - Most Efficient Windows

Energy Star highlights and publishes a list of the most efficient windows, showcasing products that offer top-tier energy efficiency and the latest technological advancements. This recognition represents the pinnacle of ENERGY STAR’s standards.

To qualify, these products must surpass the minimum qualification criteria and achieve or exceed a specified Energy Rating (ER) and U-Factor value.

Check the specs (not all window brands are the same)

Who does the ENERGY STAR certification?

When you purchase ENERGY STAR certified windows, they have been tested according to current Energy Star standards by an accredited laboratory, and the results are verified by an independent third party. In Canada, windows may be certified for energy performance by:

• CSA International (CSA)
• Intertek Testing Services (ITS)
• Quality Auditing Institute Ltd. (QAI)
• The National Fenestration Rating Council (NFRC)
• Labtest Certifications
   

What about Insulated Glass Units (IGUs)

Some insulated glass units (IGUs) may have certification from the Insulating Glass Manufacturers Alliance (IGMA), which ensures that these units will not fog and their seals will not fail prematurely. This certification is separate from the ENERGY STAR program.

The IGMA program promotes the consistent production of high-quality IGUs. Each product line is rigorously tested according to the Canadian General Standards Board (CGSB) 12.8 Standard for Insulating Glass Units, and the manufacturer must maintain a quality control program approved by IGMA. Additionally, each product line undergoes independent audits at least twice a year and is retested every two years.