The ABCs of Energy Performance

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What is energy efficiency?

An energy-efficient door or window helps prevent outside air from leaking into your house, keep heat inside, and lower electricity bills.

What is the U-value?

The U-value is the rate of heat transfer through a window. The lower the U-value, the better the window’s insulating properties.

What is the R-value?

The R-value indicates how well a window resists heat transfer, as well as the extent to which insulation prevents heat or cold from entering or leaving a house. The higher the value, the better.

What is SHGC?

This is the solar heat gain coefficient. It represents how much heat from the sun can pass through the product. The higher the value, the higher the solar heat gain.

What is the EER?

The energy efficiency ratio (EER) shows the balance between the U-value, SHGC, and air leakage. The higher the value, the more efficient the window or door is.

Double glazing vs. triple glazing

Years ago, Canadian homes had single-glazed windows. Double glazing is now the standard. We suggest you consider triple glazing for greater energy efficiency for every room in your house, or at least those that are more exposed to high winds.

LOW-E film or low-emissivity glass

LOW-E film filters most UV rays. This membrane prevents heat loss in winter and reduces the greenhouse effect in summer.

Argon gas

Our windows contain argon gas between the panes. This inert gas is a better insulator of heat than air.


ENERGY STAR® is a global gold standard for energy efficiency. ENERGY STAR®- certified products must meet very specific criteria to meet or exceed Natural Resources Canada (NRCan) energy efficiency standards.

Choosing ENERGY STAR®- certified products is a way to reduce both energy consumption and greenhouse gas emissions. Certified windows and doors are 20% and 15% more energy efficient, respectively, than traditional alternatives. You can save up to 10% on your heating bills by replacing all your windows. They also offer other advantages in terms of quality, durability, UV protection, and external noise reduction.

Certified doors and windows bear the ENERGY STAR® symbol indicating the climate zone(s) for which they are certified.

Canada is divided into four climate zones for ENERGY STAR® certification, based on average annual temperatures. Zone A is the most temperate, and zone D is the coldest. Quebec falls under zones B, C, and D only.

Learn more about Energy Star