Blog > Category > Posted: 2023-Jul-20, Updated: 2023-Nov-28

What is an R-value?

Move over, traditional window specs - the R-value is taking over the world of window sales! This rating, which has been around for a while, is becoming increasingly popular as a measurement of window efficiency. But why the sudden surge in popularity? Keep reading to find out.

Measuring heat flow into or out of a house

Are you tired of skyrocketing energy bills and fluctuating home temperatures? The solution might be simpler than you think - just take a closer look at your windows! By understanding the R-factor, you can choose windows with higher thermal resistance and better insulation properties, resulting in lower energy consumption and increased comfort. 

We all know that wall insulation is important, but did you know that the same principle applies to windows? That's where the R-value comes in -  it measures the thermal resistance and insulating properties of windows. Essentially, windows with higher R-values have better insulation, meaning they can slow the rate of heat transfer and keep your home cosy all year round. So, if you're looking for ways to boost your home's energy efficiency, don't forget about the R-value of your windows!

Whether you're an architect or a homeowner, knowing how to calculate the R-value can simplify the confusion around window specs and help you meet building code standards.

The R-value is actually calculated from the U-value, by dividing the U-value into 1, (R-value = 1/U-value).

    Example: U-value of .31 (imp.) = 1/.31= an R-value of 3.225 (imp.)

The higher the R-value, the greater the resistance to heat and the better the insulating properties. In the winter heat stays in and in the summer heat stays out.

Windows with higher R-values translate into:

  1. Lower energy consumption - Windows with higher R-values reduce the amount of heat transfer between indoors and outdoors, meaning you'll need less energy to heat or cool your home.
  2. Improved insulation - Higher R-values indicate better insulation properties, so your home will be more comfortable and less affected by outside temperatures.
  3. Reduced solar heat gain - Windows with higher R-values also reduce the amount of heat that enters your home from the sun, which can be especially beneficial during hot summer months.
  4. Greater cost savings - Lower energy consumption and reduced solar heat gain can lead to significant cost savings on your energy bills over time.
  5. Overall, investing in windows with higher R-values is a smart choice for anyone looking to improve their home's energy efficiency, comfort, and cost savings.

R-value Summary for Ottawa

  • R-value - Overall insulative value - the higher the R-value the better the window performs as an insulator.
  • U-value - Amount of heat that escapes through a window - The lower the U-value the better the insulating properties of a window

Feeling lost in the sea of R-values and window specs? Don't worry, help is at hand! Instead of guessing what R-value is right for your rooms, why not talk to your local window specialist? They're experts at finding the perfect windows to maximize your home comfort and minimize your energy costs. With their guidance, you can say goodbye to confusing specs and hello to the perfect windows for your needs. So, what are you waiting for? Start your search for energy-efficient windows today!

Related topics

What are Energy Star energy ratings?

What is a U-factor?

What is the Solar Heat Gain Coefficient?

What is visual transmittance?

What are window ratings?

CDN Energy Star Climate Zones

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