Radiant Barrier Tax Credit Info

Question: Is there a tax credit for radiant barriers?

Answer: The IRS has not issued final guidance on this issue, but it does not appear that radiant barriers will be covered.

Radiant barriers are not defined in the 2009 IECC (International Energy Conservation Code), which is a requirement of the tax credit, and they do not have an R value.

The American Recovery and Reinvestment Act of 2009 expanded the definition of insulation to reference the 2009 IECC (new language is below in red):

“any insulation material or system which is specifically and primarily designed to reduce the heat loss or gain of a dwelling unit when installed in or on such dwelling unit, and meets the prescriptive criteria for such material or system established by the 2009 International Energy Conservation Code,as such Code (including supplements) is in effect on the date of the enactment of the American Recovery and Reinvestment Tax Act of 2009,”

This FAQ will be updated as soon as the IRS issues guidance on this issue.

With vinyl siding, you can just take a circular saw and cut out a bunch of rectangles in the soffit before you install the vinyl siding. You are correct, the vinyl siding that has holes is a little lacking in open area, so you want to install a lot of it. Another option is to replace the existing soffit with a hardy board type soffit that has continuous vent holes. Finally, you can cut a hole in a porch and install an air conditioning vent grill and paint to match. It will act as several soffit vents. It’s easy and rain won’t be able to get up and inside.

An 8″ x 16″ vent provides 56 sq. inches of NFA per vent. http://www.airvent.com/homeown.....eave.shtml Note: NFA is different from the vent size. You would think that an 8×16 vent would provide 128 sq inches, but it’s only 56 of OPEN space.

Given all this, you are pretty close with 8 or 10 vents. 8″x16″ soffit vents will do the trick. If you arer using smaller vents 4″x16″ or 6″x16″ you will need more.

Thanks for the response. It confirms what I was thinking. I need to add soffit vents. How many would you recommend based on the size of my home of 1700 sq ft? I was thinking maybe 8 total. 4 on the front and 4 on the back with a large enough whole in each one to have plenty of ventilation. Of course I’d make sure to not cover the holes with insulation.

Thanks!

Wow, I think you are WAY over-thinking this. Often, there is too much emphasis on attic ventilation when installing a radiant barrier. Let me give you an example: If you park you car in the shade, does it really matter if you crack a window? Here is why. The radiant barrier rejects so much heat that usually whatever attic ventilation you’ve got is usually pretty adequate. I always recommend installing the radiant barrier FIRST. Then, put a thermometer inside the attic below the foil. If the air below the foil gets more than 15-20 degrees hotter then the outside temperature THEN increase the attic ventilation. You do not want to “seal” the AtticFoil, this is not the intention. You want air to flow freely from the bottom of the attic to the top and you want to install the radiant barrier in a way that will not impede, restrict or bottleneck the airflow. Remember, the BEST CASE lowest air temperature inside the attic is going to be the outside air temperature.

Radiant barrier will still be beneficial even with limited ventilation. I would be sure to leave a gap at the bottom near the attic insulation. Air will naturally be drawn in the bottom and head towards the top as it heats up. Here are some install instructions: http://www.atticfoil.com/radia.....uction.htm