Deciding the Direction and Angle of Installation
The angle and direction of installation is also of great importance as it will effect the efficiency of the solar collector. Naturally you want the collector to receive the maximum amount of sunlight each day and throughout the year. As a general rule if you are in the Northern Hemisphere then the collector should face South and if you are in the Southern Hemisphere then the collector should face North. See diagram below.

The angle at which you mount the collector should roughly correspond to the latitude of your location. For example:
- Melbourne, Australia has a latitude of 38o South - the collector should therefore face north at a 38o angle.
- Ottawa, Canada has a latitude of 45o North - the collector should therefore face south at a45o angle.
You do not have to be too careful about mounting the collector at the exact angle suggested. If your roof angle is within 10o+/- of your desired angle you can just mount the solar collector flush against the roof surface. The added trouble of adjusting the collector to a precise angle is not warranted as it will not result in a great improvement in efficiency.