When walking through an attic, always step on the ceiling joists, never between them. Make sure your power source can handle at least a 15 amp draw from the fan. If not, you will need to install a new circuit. This will save money by not having the fan run continuously. It also makes installation easier because no power switch will need to be installed in the house.
Heat rises, so position the fan near the top of the roof for better efficiency.
For the hot air to exit, outside air needs to come in. Make sure that your existing roof vents are large enough and not blocked by anything, such as insulation. To determine if your existing roof vents are large enough, add the total square footage of all intake vents together. The total should be at least double the area of the fan opening. To view a multimedia demonstration of this tutorial, click here .