triple pane windowsdouble pane window

Double and Triple Pane

Glass panes are the largest area of any window and the most vulnerable to heat loss and gain. To provide adequate thermo-insulation for harsh prairie climates, a minimum of 2 panes are required. Traditional 7/8″ double glazing options are used and can accommodate 1-1/4″ for all sliders and hung windows.

In areas with prolonged low winter temperatures, triple pane windows can be especially beneficial. Ecoline triple glass packages qualify for high energy-rating standards with 1-3/8″ and 1-1/4″ options available. Can be used in combination with gas injection and/or LoE glass coatings but are not necessary.

Find out more benefits of triple pane windows over double pane

What Are the Criteria for ENERGY STAR Certification?

The following technical specification determines how residential windows, doors, and skylights sold in Canada are certified for the ENERGY STAR® program. This specification is issued by Natural Resources Canada (NRCan). NRCan has been authorized by the U.S. Environmental Protection Agency (EPA) to promote and administer the ENERGY STAR name and symbol in Canada. A product must meet this specification in order to be promoted as ENERGY STAR certified in Canada.
Energy efficiency requirements for windows and doors are reflected in Table 1 and Table 2 below.

Table 1: U-factor Criteria for Residential Windows and Doors

Product Max U-factor (W/m2·K) Max U-factor (Btu/h·ft2°F)
Windows and Doors 1.22 0.21

Table 2: Alternate ER Criteria for Residential Windows and Doors

Product Min ER (unitless)
Windows and Doors 34


LoE Coated Glass

Low-emissive glass coatings help retain more interior heat than ordinary glass in cold winter months (Energy-gain) while filtering our harmful UV rays and reducing solar heat gain (Sun shield) in warm summer months. Multiple combinations of LoE glass coatings are available to achieve various levels of performance.

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Warmer in the winter

Warmer in the winter

LoE glass retains more interior heat than ordinary glass, helping to maintain a comfortable temperature.

Cooler in the summer

Cooler in the summer

LoE glass filters out harmful UV rays and reduces solar heat gain.

Energy StarNAFS 11

NAFS 11 and 2020 Energy Star® Requirements

All Ecoline windows meet or exceed NAFS 11 program standards and have achieved superior performances to meet the new 2020 Energy Star® efficiency requirements.

Argon and Krypton Gas

Argon and Krypton gases conduct up to 50% less heat than air. Using these gases to fill the spaces between double and triple pane windows protect against heat loss, condensation and cold weather for increased energy cost savings and overall comfort.

Learn more gas filling

Argon and Krypton Gas

Up to 10% Thicker PVC Profile Walls

Up to 10% Thicker PVC Profile Walls

Ecoline incorporates 7% to 10% thicker PVC profile walls than industry average for all awning, casement, casement fixed and picture windows. They are also engineering to comply with heavier, large windows and triple-glazed glasses.

True Multi-Chamber Design

True Multi-Chamber Design

To improve structural performance and sound insulation plus reduced warping, all Ecoline window styles utilize a true multi-chamber design.

Multiple Glazing Options

Multiple Glazing Options

A variety of glazing options are available for the best possible structural integrity. Traditional double glazing has a 7/8″ overall thickness (OT.) Triple glazing options are 1-3/8″ for awning, casement, casement fixed and picture windows. All triple glazing options for sliders and hung windows are 1-1/4″ with no grill limitations.

Screen Groove Port Design

Screen Groove Port Design

Casement and awning windows now incorporate a new screen groove port design for improved push-down screen fit.



Old windows don’t just lose heat, they also drain money out of your pocket. New ENERGY STAR® rated windows are specifically designed for your location.


The glass in our windows comes with a Low-E coating.

Rooms that get a lot of direct sunlight can overheat during the day. Low-E glass reflects sun rays away from the house and keeps your home comfortable.

There are different Low-E coatings based on how much sunlight you want to block. The same technology stops heat from escaping your home during the winter, reducing heating costs.

1. Solar heat 2. Visible light 3. Radiant heat

For maximum comfort and efficiency, thermal windows feature key elements in their construction:

  • High-performance triple-pane or double-pane glass
  • Argon or Krypton gas to fill the gaps between panes, making the windows even more efficient
  • Low-E coating during the winter retains heat inside while keeping the cold air out
  • Low-E glass. The same technology stops heat from escaping your home during the winter, reducing heating costs.