Should I leave the existing ventilation fans in when getting a new metal roof installed?
gc27858 asked:
I am replacing my shingle roof with a metal one. The contractor that is going to install the roof recommended that I remove the existing ventilation fans. The attic gets really hot. But the contractor told told me the metal roof will act as a good insulator and the attic fans aren’t needed. Can I get someone’s professional opinion on this. I know it would be easier for him to install the roof without the fans. But I’m not sold on the idea that the roof will insulate well enough to eliminate the need for a fan.
I am replacing my shingle roof with a metal one. The contractor that is going to install the roof recommended that I remove the existing ventilation fans. The attic gets really hot. But the contractor told told me the metal roof will act as a good insulator and the attic fans aren’t needed. Can I get someone’s professional opinion on this. I know it would be easier for him to install the roof without the fans. But I’m not sold on the idea that the roof will insulate well enough to eliminate the need for a fan.
Tagged with: Hot • Metal Roof • Shingle Roof
Filed under: FAQ
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i guess this is for your house..yes do put a fan in the roof..theymake electric ones and also something like solar.it will also keep your house cooler in the summer..believe me i went through this,,with a non working fan in the attic.actually 5 inches from my ceiling was burning up do to a non working fan,and my ac had to work double time..
I had to do it a couple months back, I left them in.
he is right on one aspect, removing them is a good idea, but you have to have ventilation, suggest a ridge vent. if he doesn’t know what that is, get a new roofer. if you do not vent the roof, you will have a lot bigger problems
You have to have ventilation. Metal is not an insulator, it’s a conductor. If it’s shiny it will reflect, but it won’t stay shiny. If there is insulation under the metal, then the reflective quality will be helpful, but if not, the metal will heat up and it will get hotter than hell in your attic, and make your AC work harder. The more ventilation you have, the better. Ridge vents are good.
The problem with your existing fans is that they were made to install on a shingle roof, and the flange is probably full of nail holes and roofing cement, and hard to tie in on a metal roof. They can probably be modified in various ways, (e.g. curb mounted), by a good sheetmetal mechanic to work with a metal roof, and hopefully, your roofer is a good sheetmetal mechanic. Alternatively you could put gable fans, if you have gables.