Looking for some advice on my attic fan. I just replaced my roof and eliminated the gable venting and switched to continuous soffit and a ridge vent. Now, I am in the process of getting new siding. One of the workers told me that I need to vent the fan outside to remove the hot air. Is the Ridge vent not enough? I was going to try to build a "box" around the fan and use 10" or 12" in flex duct and vent it to a new gable vent. This gable vent is only piped to the fan. Is that the way to go, or is it overkill? I plan on adding insulation to the attic latter this year. The fan is an old 36" model. Thanks for the advice.
You're doing it the right way, at least for anyone who gets cold winters and snow. Mine was vented straight up through the roof, and was constantly creating it's own little shower in the bathroom. I revented it to the gable, through insulated pipe, with more insulation wrapped around it, and it has given no problem for two years. Remember to slope your pipe to the gable. Good luck!
Ridge vents allow for the natural draft effect because hot air rises, if your soffit vents are clear to allow fresh air to be pulled in. I would recommend that you keep a gable vent with a fan if your summer weather is hot. The heat in attic spaces is what causes shingles to brake down, so in the south, a 30 year shingle last about 20. You can wire the fan through a thermastat so that it only kicks in when the heat inside the attic space gets to 100 degrees. These measures will lower your cooling cost as well as extend the life of your roof shingles. From your comments, you just had them replaced I believe. In addition, when you add insulation, consider the crawl space below the house as well, that is the floors.