if so then i lived there for 6 months

I too am trying to figure out the benefits of Radiant Barrier, but from what I understand, installing a barrier under shingles is not a true Radiant barrier but a thermal barrier. Radiant barrier requires air on one side, like when you install it inside your attic crawl space. So I don't know if it qualifies for the credit or not. I would contact the correct govt agency first. I stumbled across this blog post the other day about this. http://www.radiantbarrierguru.com/radiant-barrier-under-shingles/

Hope that helps
Steve

Steve- your absolutely right. Polaralum is not a radiant barrier when installed over the decking under shingles. I know the company claims that it is a "thermal barrier" but I would think that the reflectivity of it could backfire as a thermal barrier. I just wouldn't trust it. The only way to do it right in on the rafters in the attic.

The only way this product makes sense is possibly under some type of metal or tile roofing where you can achieve an air space.

There are a lot of reflective barrier products. They've been around for 40 years or more. All of them have "documented" claims of added R value and energy savings. In the lab and some times on jobs they do help save some energy but at a very high cost. If you intend to use one, shop the price and get some testing information. Testing should be done by a major testing lab, not Joe Smiths local testing company. Consider adding more insulation in your attic and weigh the cost between the barrier and added insulation. You know that the insulation works if done properly.

LOL I love how these new members pop up and hype a new product.