Thinking of replacing your windows but confused by all of the terminology surrounding new windows? You’re not alone. As energy saving innovations have improved, understanding window replacement has become a bit more complicated. Let’s try to clarify some of the window lingo.
Frame: window frames are available in a variety of different materials including wood, clad wood, aluminum, vinyl and fiberglass. Each of these materials has its pros and cons in both aesthetics and energy efficiency.
One of the most common frame materials for replacement windows today is vinyl. According to the CMHC, good quality “vinyl frames are very durable, and low maintenance–they can resist color fading, moisture, termites, corrosion and air pollutants.” If you are selecting vinyl windows, those with an insulated or reinforced cavity in the sash and frame provide the best energy efficiency through better insulating qualities.
Glazing/Glass/Panes: the glass separating the indoors and outdoors.
Double-pane or double glazed windows have two layers of glass, separated by a spacer. The space between the panes of glass is filled with air or an inert gas such as argon (see below).
Triple-pane or triple glazed windows have three layers of glass. The extra pane and air space generally provide better insulating values making this a better option in extremely cold climates.
Inert gases such as argon, and occasionally krypton, are sealed between the panes of glass. Inert gases are denser than air so their insulating value is higher and they transmit less heat/cold between the panes of glass. (In window jargon, you may hear this referred to as having “lower thermal conductivity”.) Gas filled windows are slightly more expensive than air filled but they will help with energy loss and are considered cost-effective.
Low-E (Low-emissivity) is a thin, invisible coating that allows light to come through but filters out UV rays and prevents the transmission of heat. It is used in double-glazed windows, giving them similar insulating properties as triple-glazed windows but at a lower cost.
When shopping for new windows, the terminology can be overwhelming. Take the time to brush up on the lingo before you hit the showroom and don’t be afraid to ask the salesperson to clarify any points that you don’t understand surrounding the construction, installation or energy savings of the windows you are looking at. When it comes to home improvements, buying new windows is a big investment and is done infrequently so take the time to understand your decisions.
Note: When considering window replacement, make sure that your windows come with a warranty from either the manufacturer or contractor.
Related blog article: Understanding Home Energy Audits