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Personal: Residential

Buying Energy-Efficient Windows, Doors or Skylights is Easy With ENERGY STAR®

Windows, doors and skylights are among the growing list of products that can qualify for the ENERGY STAR international symbol for energy efficiency.

Step One

Find the zone where you live or where the product will be installed. Canada has been divided into four climate zones based on annual average temperature. Zone A is the mildest, and Zone D is the coldest.

Climate Zones

Step Two

Look for the ENERGY STAR symbol in the showroom or on promotional literature, or ask your salesperson, contractor or renovator.




Samples of ENERGY STAR labels

Sample of promotional label

Sample of promotional label

Sample showroom display label

Sample showroom display label

Step Three

Make sure that the product model you are buying is qualified for the correct zone, or, to save even more energy, for colder zones. If you live in a location that is significantly higher in elevation than the surrounding area, consider purchasing a product that is ENERGY STAR qualified for at least one zone colder than where you live (especially in southern and central British Columbia).

List of heating degree-day values by province/territory and zone

View our list of manufacturers and dealers that supply ENERGY STAR qualified windows, doors and skylights and have joined as ENERGY STAR Participants in Canada.

Energy-efficient fenestration products will:

  • reduce your home energy costs by 7 to 12 percent
  • reduce or eliminate cold drafts
  • collect less condensation
  • reduce noise from outside

ENERGY STAR Performance Levels

ENERGY STAR qualified windows, doors and skylights are tested and certified by an independent, accredited agency. Products qualify for ENERGY STAR based on either their U-value or their Energy Rating. As well, windows and patio doors must achieve at least an A2 rating for airtightness. The tables below show the required ratings for windows, doors and skylights to be ENERGY STAR qualified for each climate zone in Canada.

ENERGY STAR Requirements for Windows and Doors

(Products may comply based on either their U-value and R-value or their Energy Rating)
Zone Maximum U-Values and Minimum R-Values Minimum Energy Rating (ER) Values (Maximum U-Value 2.00 W/m2.K)
  U-Value (W/m2.K) U-Value (Btu/h.ft.2F) R-Value (ft.2.h.°F/Btu)   (Most Windows and All Doors) (Picture Windows Only)
          1998 2004* 1998 2004*
A 2.00 0.35 2.9 or –16 17 –6 27
B 1.80 0.32 3.2 or –12 21 –2 31
C 1.60 0.28 3.6 or –8 25 +2 35
D 1.40 0.25 4.0 or –5 29 +5 39

*The methodology used to calculate Energy Ratings, as defined by the Canadian Standards Association, was changed in 2004. All windows and doors now have positive ER numbers.

ENERGY STAR Requirements for Skylights
Zone Maximum U-Value (W/m2.K) Maximum U-Value (Btu/h.ft.2F) Minimum R-Value (ft.2.h.°F/Btu)
A 3.10 0.54 1.8
B 2.80 0.50 2.0
C 2.60 0.46 2.2
D 2.38 0.42 2.4

Technical specifications for manufacturers