Foil insulation barriers
Hobart9032
| Posted in Energy Efficiency and Durability on
I have been looking at your site and find most questions and answers very out of date relating to this subject.
I have just attended a dinner seminar with SMART ENERGY TODAY.
I would like an update on your most recent findings on this subject and any information of the above company.
Thank you.
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Replies
Dinner seminar. Mmmm! How was the food?
Richard,
Which questions and which answers were out of date?
Richard,
The information in this article is up-to-date: Radiant Barriers: A Solution in Search of a Problem.
I visited the web site of the company you mention and read, "The technology behind Sol-Blanket Insulation was initially created by NASA..." To me, this sentence is a red flag meaning "Danger ahead. Exaggerations coming."
Then I read, "While the actual R-Value of Sol Blanket is relatively low, the Effective R-value is around 13 when it’s reflective properties are calculated in." Uh oh! Watch out! "Effective R-value" (a phrase with no legal definition) has been introduced!
On a web forum I found this question: "Are Smart Energy Today Inc. dinners high pressure?"
I read some answers:
"I would say if you expect a company to give you a free meal at a show and tell and don't expect it to be a hard-sell, you are deceiving yourself."
Another answer:
"Total Scam. They offer a free home energy audit. All the rep did was push financing options on us. He wanted us to give him a $2000 check that night to lock in the special discount on installation that was only available that evening. My wife and i would then have 30 days to come up with the other $23,000 in financing. Or if we wanted, he just happened to know people that could set the financing up for us."
Of course, there was also a positive review -- posted by Smart Energy Today.
Their web site has a mix of good and bad information. A sample:
Good: They note that radiant barriers are best where you want to stop heat flowing downward. That's true and is one of the key reasons they are rarely worthwhile. Other types of insulation are equally helpful for heat flow in both directions, but radiant barriers are not. Not mentioned is the fact that in the pacific northwest, their region, heat flow downward in an attic is not a major problem, as the number of days when cooling is needed is very limited, whereas heatflow upward is an issue all winter. So a radiant barrier in the attic would be a very poor choice for an attic in their region. And that's my review of the information on their page that I thought was the most helpful and accurate!
Bad: They recommend laying the radiant barrier on top of the attic insulation. The problem with that is the bottom surface is not facing an air gap, so it has little benefit. And the top surface will get dusty within a few years, and will stop being effective. So within a few years, the remaining benefit is only that of the 8 mm thick conventional insulation between the two radiant barrier layers.
A mix of good and bad: They say their radiant barrier is better than others because it has 8 mm of conventional insulation between the foil layers. That's true--8 mm of real insulation is better than nothing. But you could probably get 8 inches of cellulose insulation for the cost of their 8 mm of insulation, and get 15 to 20 times higher R-value.
They haven't even bothered to run third party ASTM C 236 and ASTM C 976 (required by the FTC) or ASTM C1313, ASTM C1321or ASTM C1224 testing on their product as a radiant barrier, or at least I couldn't find evidence of ANY testing of that product on the web. Or maybe it's sub-standard even as a radiant barrier, perhaps insufficient reflectivey or maybe it has a tendency to delaminate? No tested fire ratings?
Why bother paying for testing when you can spend that money on marketing dinners?
Usually when r.b. vendors make "Effective R-value" claims there is a testing company document describing the conditions under which that performance is valid, yet effective R13 claim here seems to be simply an unsupported claim.
IMHO: Same crap, not even different piles. Nothing to see here.