Awnings are not only architectural devices that add to the beauty of a building but also significant factors in regulating the temperature inside the building. When installed at a proper angle, awnings effectively block the hot midday sun.
Awnings affect the appearance of a house. Therefore, aesthetic considerations will play a role in determining the angle between the awning and the building. From an aesthetic point of view, the best angle is 45 degrees, according to the California Energy Commission.
In the North Temperate Zone, the hot midday sun shines on windows on the south side of the house, so these houses need awnings more than other houses.
Midday Sun's Angle
The angle at which the sun strikes the window at midday depends on the season of the year and the latitude at which the house is located. A well-placed awning will block the hot sun in the summer, when the sun is higher in the sky at noon, but will allow the sun to shine into the house in the winter, when it is lower in the sky at noon.
Forty-five degrees is the best angle for awnings. It is better to retain this angle for houses in all north temperate latitudes and to adjust the length of the awning, making it the right length to block the sun in the summer and allow the sunlight to enter the house in the winter.
- InspectAPedia: Passive Solar Design Roof Overhang Explanation & Design Details
- Pilkington: Designing with the Pilkington Sun Angle Calculator
- Florida Solar Energy Center: Technique for Shading Residential Walls and Windows
- New Mexico Solar Energy Association: Passive Solar Design Primer
- "Building Systems for Interior Designers"; Corky Binggeli; 2010