Summary of qualifications—windows, doors and skylights

ENERGY STAR® requirements at a glance

ENERGY STAR High Efficiency


Manufacturers should consult the complete ENERGY STAR® technical specification.

As a keen shopper, you may want to know the basic ENERGY STAR requirements for fenestration products in your climate zone.

Fenestration products can be certified for ENERGY STAR if they have:

  • a high Energy Rating (ER)—ER balances heat loss with heat gain. The higher the ER value, the more energy efficient the product. (ER ratings do not apply to skylights.)
  • or
  • a low U-factor—U-factor measures the rate of heat transfer. The lower the U-factor value, the better the product insulates.

The tables below show the ratings currently required for ENERGY STAR certification for windows, doors and skylights in each of four climate zones in Canada.

Note that these ratings are for the entire product. Energy efficiency ratings for the glass portion only, often called “centre of glass” ratings, can make a product seem more energy efficient than it is.

Windows and Doors

Heating Degree-Day Range Compliance Paths
Energy Rating (ER) or U-factor
Minimum ER (unitless) or Maximum U-Factor W/m2•K
and Minimum ER (unitless) Windows and Sliding Glass Doors Only
1 < 3500 25 or 1.60 (0.28) and 16
2 3500 to < 6000 29 or 1.40 (0.25) and 20
3 ≥6000 34 or 1.20 (0.21) and 24


Zone Heating Degree-Day Range Maximum U-Factor
1 < 3500 2.60 (0.46)
2 3500 to < 6000 2.40 (0.42)
3 ≥ 6000 2.10 (0.37)

*The requirement for tubular type skylights for all 3 zones is 2.60 (0.46)

Windows, doors and skylights must also have an air leakage value of 1.5 L/s/m2 or less.

Find your zone on the ENERGY STAR climate map.

Read more details on ratings and standards.

The ENERGY STAR name and symbol are trademarks registered in Canada by the United States Environmental Protection Agency and are administered and promoted by Natural Resources Canada.