A couple of months ago, I wrote about why you don't want power attic ventilators in your home. Whenever I've written about this topic, it just seems to set some people off. I get comments like, "You really should do more research before you post blogs like this," and, "You don't know what you are talking about!" My favorite, I think, was, "You need to go get some more degrees!" (Sorry. Ain't gonna happen. I've got plenty of learning left to do, but I'm done getting 'lettered,' as another commenter in our blog put it.)
In my last article, I also quoted the esteemed Dr. Joe Lstiburek (who also doesn't need any more degrees) and referenced research on the topic by the Florida Solar Energy Center. This isn't just my idea, you know. It's basic building science.
Today, let me just say that home builders in Georgia, as of 1 January 2011, cannot install power attic ventilators in the homes they build. Well, OK, that's not quite correct. Builders can install them. They just can't give them any electricity from the power company. Here's what it says in the Georgia State Supplements and Amendments to the International Energy Conservation Code (2009 Edition):
403.10 Power attic ventilators. In new construction, power attic ventilators shall not be connected to the electric grid. Power attic ventilators connected to a solar panel are allowed.
You can download and read the document (pdf) yourself if you'd like. You'll find the above passage on page 13, near the bottom. This is basic building science. It's not something like, say, crawl space vents, that's based on speculation without any research behind it. And that part about solar-powered attic ventilators being allowed was mainly a compromise, from what I understand. They can create the same kind of problems as their grid-tied brethren and should be banned, too.
So, if you're a home builder in Georgia or looking to get a new home built in the state, be aware of this new provision in the Georgia energy code. In my opinion, this is a great advance for homebuyers here and is another way that Georgia is leading the United States in applying building science to home building. As I wrote recently, you're free to disregard the laws of building science. When building science becomes state law, however, it's a bit harder to get around it.