Great solution to moving air through your attic during all times of the year. This is the best one that we found on the market so far and it was very easy to install on the roof. With the template provided and having the recommended tools, this should take your 2 to 4 hours to install. The solar powered fan provides cooling of attic spaces in the summer, which prolongs the life of your roof and reduces heat transfer to the rest of the house keeping it cooler. In the winter, the unit moves air through the attic to keep it free of moisture and also prolongs the life of insulation and prevents water from condensing in the attic causing damage. A great way to get active air movement without paying an electric bill over the lifetime of the unit. Check out their products.