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Energy-Efficient Window Terms Explained

Jun 2, 2023 | NFRC Rating System

Content courtesy of Energy Star

Energy-Efficient Window Terms Explained.

Updating or installing new windows for a new residential or commercial build requires a bit of a learning curve to understand the “science” behind an energy-efficient window.  When speaking with a window consultant you will come across certain terms pertaining to the design of the window frame, glass and spacer systems.  We’ve gathered together some of the most used terms when discussing an energy-efficient window and it’s components.

LOW-E GLASS
Low-E (low-emissivity) glass has been treated with a microscopic metallic coating designed to filter the amount of UV light that enters your home. By filtering the amount of UV light that enters your home, it keeps the heat gain lower in warm seasons and allows more heat in during cooler months. This keeps your home’s temperature more consistent year-round. By filtering out UV light, low-E glass also prevents fading on your furniture and window treatments.

U-FACTOR
U-factor measures the rate of heat transfer and how well a window insulates. It is measured on a scale from 0.20 to 1.20. The lower the u-factor, the more effective the window is at insulating.

R-VALUE
R-value refers to a building material’s insulation level. Each region of the US has an energy-efficient r-value range for windows based on that area’s climate.

ARGON GAS
Argon is an extremely dense colorless, odorless gas with very low thermal conductivity. It is used as insulation between double-pane and triple-pane windows. When paired with Low-E glass, it keeps the window closer to room temperature, helping eliminate drafts and increase energy efficiency.

WARM EDGE SPACER SYSTEM
Spacers are placed between double and triple-panes of glass. In the past, they were mainly made of aluminum, which we no longer recommend due to its poor insulating properties. Our Intercept™ warm-edge spacer system extends the shelf-life of window glass by reducing condensation build-up and edge-to-glass temperatures. Designed to seal in escaping heat, this spacer system is the most effective on the market.

At Westeck Windows and Doors, we manufacture bespoke fenestration products that will provide benefit to the specific needs of the project. Working with main contractors, architects, designers and clients, we recognize the requirements of each development are unique, and provide a custom solution to suit.

Westeck manufactures innovative windows for maximizing the view, ease of operation and impressive thermal performance.

If you or your architect can design it, our specialty department can most likely build it.

Westeck Windows and Doors now has 30+ sales professionals, across offices in BC – Vancouver, Chilliwack, Victoria, Nanaimo, Kelowna and Washington State – Kirkland and Bellingham

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