Blog post by Brianna O’Brien
On hot summer days, air conditioning can account for roughly one-third of electricity use in Ontario. But did you know that a simple awning can reduce cooling energy use by as much as 15%?
The awning is not a technical marvel, but they are remarkably effective. A little bit of shade can cut air conditioner use dramatically, which can save you money. Air conditioner use in the summertime can add an extra $200 to your energy bill.
The Evidence
The Canadian Centre for Housing Technology tested the energy-saving ability of awnings by comparing two houses. Cooling energy use was monitored after installing awnings on one of two nearly identical houses. The experiment found that the air conditioner in the house with awnings used 15% less energy than the one without awnings.
Additionally, as solar radiation increased, energy savings from awnings increased. Over the experiment period (May 17 – September 20, 2010), the estimated total energy saving awnings provided by reducing air conditioner and fan use was 401 kWh. This is about the same amount of energy an LED light bulb uses over 9 years.
On average, the house with awnings was 1.0 °C cooler. Awnings reduced the temperature for the whole house, not just rooms with awnings. A study in the U.S. found that across 50 cities, awnings could save up to $200 annually in energy costs per household.
Installing awnings above south-facing windows can reduce heat gain by 65%. On east and west-facing windows, awnings can reduce heat gain by up to 77%. South, west and east-facing windows should be prioritized since they receive the most sun.
The Options
Fully retractable awnings are best for allowing winter sun in and keeping the summer heat out. Retractable awnings can be motorized to retract in seconds which provides greater convenience.
Retractable awnings are the more expensive option. They can cost thousands of dollars for motorized models. Retractable awnings that use a hand crank instead of a motor are typically cheaper and start around $500.00.
Fixed aluminum awnings are robust and require less maintenance, but they cannot retract fully to let the winter sun in for warming. Fixed awnings should be set at an angle of 45 degrees in northern latitudes to allow the sun in during the winter while blocking it during the summer.
Awnings can be bought and installed by contractors located in Waterloo Region. They can also be customized to fit your specific style and preferences. As a starting point, check out Reep’s Contractors List.
Other shading devices like fixed outdoor overhangs have not been shown to prevent overheating during the summer months. Additionally, studies of indoor shading devices such as blinds, shades, and curtains found there were little energy or cost savings when these devices were implemented. Awnings, however, have been proven to reduce indoor temperatures while also providing long-term cost savings.
