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quentin Posted: Oct 08, 2008 04:33 PM	R-value issue I was talking to a local builder that is interested but was a bit fustrated at a few points. He was asking to compare my foam to Icybunk and it took a while to get through to him that half pound is half pound is half pound and the idea of 2lb took some work too. It seems the local Icy dealer has convinced him that an R - 20 of half pound is as good as an R - 38 like code requires. I have no idea if they have actually gotten this past the code boys or not but it made trying to explain that idea a bit difficult. I just pointed out that yes it was good but I would not put half pound as being that good and that if a code official would agree to it then fine but unless the bode boys agreed it could be a problem for him to trust that number. Is that claim realistic in truth or is my personal belief of R - 30 much closer in the equivilent?
JohnPeters Posted: Oct 11, 2008 07:40 PM	No S*^t...I have been up against the wall with some icy bunk dudes around here. I wonder if our situations are related. While I recognize how great icybunks presence has been in the market place for developing awareness about SPF - i opted not to spray their products. I found their product offering as well as building science knowledge to be too one dimensional for my liking. Now, recently I have been losing bids to some icybunk contractors and I cannot figure out how. I know that my icy-competitors cannot compete with my price point. I also know that with out a 2"x"12 roof deck joist, icy cannot reach R-38. Safe to say that no jobs i have lost utilized 2"x12" roof deck joists. How can they be beating me? One of them offers closed cell, but I know they never spray it... You got me thinking now Quentin. Has icybunk corporate got their contractors to weasele their way around code? My hunch was that when a customer compares my estimate to an icybunk estimate, apples are not being compared to apples. Your post is validating my thoughts. Anyone else out there seeing the same thing? Anyway - back to your post. I would say that R-25 of any density of SPF will out perform R-38 of filter glass all day long.
mason Posted: Oct 11, 2008 09:50 PM	Check out my article on Learning the Difference Between 1/2 lb and 2 lb foam on my website. Also check out the article on R values. masonknowles.com Both closed cell and open cell foam perform 20 to 40% more efficiently than fiberglass when air infiltration and convection are considered in determining energy efficiency. Tests conducted at Oakridge National Labs attic simulator and tests conducted at Architectural Testing Inc. confirm and quantify it. However, the closed cell foam performed slightly better than the open cell in the tests. I attribute it to small voids that were discovered in the open cell foam after the tests were conducted.

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Comments

quentin

Posted: Oct 08, 2008 04:33 PM

R-value issue

I was talking to a local builder that is interested but was a bit fustrated at a few points. He was asking to compare my foam to Icybunk and it took a while to get through to him that half pound is half pound is half pound and the idea of 2lb took some work too. It seems the local Icy dealer has convinced him that an R - 20 of half pound is as good as an R - 38 like code requires. I have no idea if they have actually gotten this past the code boys or not but it made trying to explain that idea a bit difficult.

I just pointed out that yes it was good but I would not put half pound as being that good and that if a code official would agree to it then fine but unless the bode boys agreed it could be a problem for him to trust that number.

Is that claim realistic in truth or is my personal belief of R - 30 much closer in the equivilent?

JohnPeters

Posted: Oct 11, 2008 07:40 PM

No S*^t...I have been up against the wall with some icy bunk dudes around here. I wonder if our situations are related.

While I recognize how great icybunks presence has been in the market place for developing awareness about SPF - i opted not to spray their products. I found their product offering as well as building science knowledge to be too one dimensional for my liking.

Now, recently I have been losing bids to some icybunk contractors and I cannot figure out how. I know that my icy-competitors cannot compete with my price point. I also know that with out a 2"x"12 roof deck joist, icy cannot reach R-38. Safe to say that no jobs i have lost utilized 2"x12" roof deck joists. How can they be beating me? One of them offers closed cell, but I know they never spray it... You got me thinking now Quentin. Has icybunk corporate got their contractors to weasele their way around code?

My hunch was that when a customer compares my estimate to an icybunk estimate, apples are not being compared to apples. Your post is validating my thoughts.

Anyone else out there seeing the same thing?

Anyway - back to your post. I would say that R-25 of any density of SPF will out perform R-38 of filter glass all day long.

mason

Posted: Oct 11, 2008 09:50 PM

Check out my article on Learning the Difference Between 1/2 lb and 2 lb foam on my website. Also check out the article on R values. masonknowles.com

Both closed cell and open cell foam perform 20 to 40% more efficiently than fiberglass when air infiltration and convection are considered in determining energy efficiency. Tests conducted at Oakridge National Labs attic simulator and tests conducted at Architectural Testing Inc. confirm and quantify it.

However, the closed cell foam performed slightly better than the open cell in the tests. I attribute it to small voids that were discovered in the open cell foam after the tests were conducted.

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