R A
1/27/2013
I read through some of the previous issues with condensation, and will continue to read through others, but the general consensus is that one needs good venting and good insulation, and maybe a vapor barrier between the ceiling and attic. I recently installed a new exposed fastener metal roof over one layer of asphalt shingles. I installed 30lbs felt between. During this process, I pulled two whirly bird vents for the more commonly installed ridge vent for metal roofs. I couldn't find much information about keeping whirly birds with metal, and most people that I either spoke with or read about online said go with the ridge vents. I did the installation with a friend who has done a number of other metal roof installs. Now that it is January I'm starting to get some condensation. I have soffit vents, and 18" of insulation, and no history of condensation with the previous asphalt roof. The whirly birds seemed to do the trick. So my question is, I have windows in my gables, which I could transform to gable vents, or this summer, I'm wondering if I should figure out how to reinstall the whirly birds? When I had a house inspector look at the home 4 years ago before we bought it, he mentioned that whirly birds were superior to ridge venting, he also didn't like metal roofs, because they looked funny. My thought was that it was environmentally a smart decision. My home has 16 inch walls, with lots of passive solar and great installation. Along with this, I felt a metal roof would be a great investment and compliment the house well. Any advice or help would be great. I'm stressed that I'm going to get mold, like so many others have mentioned. The condensation isn't too bad yet. Thanks, R
Todd Miller
Classic Products, Inc.
1/28/2013
Tell me more about your soffit vents. How many do you have? Have you made sure they're open and not blocked by insulation?
R A
2/20/2013
Sorry for the late reply. The soffit vents are clear and open. THey are an older aluminum style soffit vent, that allows air in the outer 4 inches or so on the outer edge of the soffit, they run the entire length of the roof 40' both sides. Inside, I have the 3' or 4' foam rafter vent guides, or whatever they are called. I can see the glow of daylight just beyond them. So there is no insulation getting in the way. I do have a chimney running through the attic, and it can get warm, as we heat exclusively with wood. I also have a duct tube from a bathroom vent, running just under the insulation. Wondering if I need to wrap that with insulation, or inspect it for leaks.
Todd Miller
Classic Products, Inc.
2/25/2013
I tend to think you do have some air leakage into the attic. I would insulate those pipes / chimneys and look for other sources.This is odd. Whereas it sounds like you need more exhaust ventilation I am a little concerned about the air patterns that would be created by opening up your windows to be vents. Do you feel confident the ridge vent was installed properly and functioning? You may want to buy a smoke pen so use in the attic to see how your air is traveling.

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