Energy Star Roofing for Minnesota
So, I have a 1.5 story 1920 home in Minneapolis, with two bedrooms upstairs. The current roof is shingles that are a light-medium gray installed over the original roof deck (boards). It may soon be time to replace the roof and I am curious about using energy star roofing due to summer heat gain. The house has blown in cellulous insulation in the area above the upstairs ceiling. In the attic spaces there is open cell foam on the roof deck. Much of the ceiling is sloped, so there are 2×4 rafters with the cellulous and then the plaster ceiling. The house has forced air with AC, but the duct routing to the upstairs is a bit convoluted due to the retrofit, resulting in fairly low flow to the upstairs. In the summer it gets a bit warm up there due to the low air flow and the heat gain from the roof doesn’t help. So, I was thinking as long as I was going to replace the roof, energy-star shingles might help a bit… What I would really like to do is put some foam boards above the existing roof deck, install plywood over that, and then the shingles, but I have exposed rafter tails and I’m not sure how you could add all that thickness to the roof without making it look goofy. Any input? Thanks, Erik
Replies
I'm new the the energy star
I'm new the the energy star roofing industry applied to residential ... so I'm going to 'think outloud a bit'. It is my understanding that an Energy Star roofing product ... is primarily for the cooling (as you said). I looked up a list of approved manuf. It doesn't tell me what KIND of roofing they have, but it was obvious some were e.g. metal roofing.
Based on my past knowledge, I don't think there would be an asphalt shingle that meets an energy star requirement. Inherently, ashphalt shingles tend to absorb heat ... yes even 'white' ones (which if I recall only showed a neglibible higher reflectivity over darker shingles).
So ... an energy star roof will likely be a different roofing material than what you might think. Research is in order IMO.
Somewhat off topic, but I too have upstairs rooms. One partial solution to the airflow issue is to install in line duct booster fans that come on when the furnace blower does. it greatly helped our situation in both winter and summer and they are cheap. maybe $60 bucks for two of them at Homer De Pot.
IMO that comment is relevant. Sometimes people are looking for solutions to problems in the wrong place. I'm not implying the poster did this ... just that there is often a couple of ways of looking at solving the problem. The method(s) chosen by the poster aren't always "the right" solution ... just the one the poster has assumed to be 'his only option'.
Good call and good alternative! Important to open the perspective on any topic, I think. That's the purpose of the forum to get wide feedback, not just have everyone have the same tunnel vision.
Erik,
Have you used up your $1500.00 Energy tax credit yet? Ask your roofing contractor to price out these Solaris shingles: http://www.remodeling.hw.net/roofing/certainteed-landmark-solaris-reflective-asphalt-s.aspx
They have a special reflective granule, but I'm not sure if they are available in MN. C-teed also makes a "star white" color that qualifies for the tax credit that costs the same as regular colors, ( Solaris about doubles the cost of regular color).
There are at least three manufactures of energy-star roofing shingles (Certainteed, Owens-Corning, and GAF). The corning ones are only available in the SW according to their web page, not sure about the other two.
I have toyed with the booster fan idea before, will probably do that too but if I have to put a roof on anyway, wouldn't it be nice to use a product that will help reduce the load on the A/C at the same time?
Thanks
Erik
Well, given the fact that you are in Minniapolis and your heating season runs from Oct to May, it might not be the best thing in the world to reduce your solar heat gain for the 20 days in the summer it actually gets really nasty.