Icynene Insulation - Is it worth it?

[Jeff Skelton]

I am doing a remodel where I am going to have cathedral ceilings and I am trying to figure out how I am going to insulate the ceilings. I am considering using Icynene. I have an estimate of around $1.70 per foot. I hear and see everywhere about how expensive this is compared to batts or cellulose insulation. However, I can not quite see how it is 3x more expensive or, even, how it is more than rigid panels. If I look at batts or cellulose or fiberglass UNistalled I see this but the price for Icynene is an installed price. My question I guess is does anybody know what the true comparison would be for Icynene version cellulose/batts/fiberglass installed or has anybody done this comparison?

My problem is a little more complex because I have the cathedral ceilings. I will need to build them down to get the depth for the r-value code. So I have the time and materials for the build down plus the insulation plus the time to fill the void or cut and staple the batts. Given all this it seems that Icynene is an equal value. What am I missing here?

[Edwin Pawlowski]

Compare the R value of the installed products. If product "A" is going to have a final value of R6 but another is going to be R15, you can see the cost would be different. It may or may not be a better value Ed

[m Ransley]

Pink or blue foamboard are R 5 per inch ,, The foilfaced foamboard is R

7.2 per inch . Icynene is apx R 4.2 per inch . Fiberglass batts apx R 3.5 per inch.. Look into the R 7.2

[m Ransley]

You said 1.70 per foot but you didnt say what thickness or R value. Still R4+ for Icynene R 7.2 for the good board

[William W. Plummer]

When I looked into icynene (same as isocyanate?), the manufacturer advised me to avoid it in existing construction because it was likely to expand and pop off the wallboard.

[Jeff Skelton]

I did not mention R value for a couple reasons.

1) because I will make up for lower R value through less infultration. By code, I can get away with using Icynene in the 6" rafter with a lower R value because I effectively seal all leaks. My R value will be R-21 or 25. Code is either R-30 or 38. If I do not use Icynene then I need to build down to get the depth. 2)For me the overall difference with R value is not huge. I live in the Pacific Northwest so the temperature difference is not severe. If I lived where it got below 0 or over 100 then the difference in R value would be more of an issue.

Also, this remodel is a new second floor addition so no worries about expansion.

[m Ransley]

Air infiltration is not R value if your code is r 38 someones lying to you. Also that is a Minimun for code, more is better. Plus you need an airspace on your cathedrial ceiling or you roofing wont last

[m Ransley]

If you go under code what will your inspector do , will you get your completion certificate ?