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steven argus
Posted: Sep 01, 2010 04:47 PM
Performance rating?
Mason, A few years ago, I heard rumors of droping the antiquated "R" value system and moving to a "performance" rating system for ALL insulation. Any news on this? If we can get prices down, maybe we can afford to install Mike's paint. (just kidding, Mike- just a little friendly hazing)
mason
Posted: Sep 01, 2010 05:10 PM
They will never drop the R value requirements and ratings but most building scientist now realize that air infiltration, thermal bridging, convection currents, wind washing, varying temperatures (hihg and low), high moisture content, etc. all affects the insulation's performance.

Joe Lstiburek has proposed a new performance metric called the Thermal Index which takes all of these factors into consideration when evaluating a building assembly. In the Thermal Index you start off with the insulation material's rated R value. Then through performance testing like the type SPFA did at ARchitectural Testing Inc. you deduct a percentage of the R value that is affected by all of the mitigating factors in your specific climate. So for example in a cold climate you might have a different thermal index than in a mixed climate or a hot humid climate.

Check out my presentation SPF Today and Tomorrow on my website masonknowles.com for more information on this and other trends.
jimcoler

I have over 10 years of experience specifying and installing open and closed cell spray foam. I've sold my business but I'm still selling for the new owners and consulting on large and custom specific jobs. 

I've expanded my knowledge into t

Posted: Sep 02, 2010 10:53 AM
Mason,
Statements like this are very discouraging!!! " They wil never drop the R value requirement". I can't believe you can see into the future and know for sure that they will never change it! We talked about it at the last SPFA conference and wanted it changed to a better insulation measurement system. I would propose a convective, conductive, and radiant heat with a factor included for thermal mass. This could be called what ever you want, but I would call it I factor for Insulation Factor.

You explain many of the descrepencies of the current R value test method and I thick they should be address on an equal and level playing field! Enough of the bowing to the politics of the fiberglass companies and out with the bad!
steven argus
Posted: Sep 02, 2010 03:18 PM
Why can't the test that determines "R value" be more realistic? Insulation is expected to perform in all conditions. Why can't the testing reflect that? (fire testing too)
mason
Posted: Sep 03, 2010 12:19 PM
Jim,

What I meant is that the building codes will keep the mandatory R value tables, But I am not saying that other factors will not be added to the codes that would allow alternate test methods to show how you can achieve equivalent energy performance.

For example, when I was head of SPFA, we talked to the ICC Evaluation Services about getting a new Acceptance Criteria for a modified ASTM 1363 test procedure that measures the energy performance of wall assemblies at high and low temperatures and adding air infiltration into the mix. This is the testing we did at Architectureal Testing Inc. that demonstrated that sprayfoam kept 100% of its rated R value in high and low temperatures with a wind load while fiberglass in the same conditions only kept 50 to 70% of their efficiency.

If this could be approved, then a supplier can test their sprayfoam insulated wall assembly and obtain an evaluaton report that stated at a specific thickness of SPF in this climate in this assembly, they would not have to meet the prescribed R value tables in the code because it gave performance better than the prescribed R value tables.

That is the way I see our industry being able to obtain a fair playing field.
steven argus
Posted: Sep 03, 2010 05:52 PM
Well now, let's get crackin! What steps need to be taken to get this approved? Where can we get a copy of these test reports?
mason
Posted: Sep 03, 2010 10:10 PM
You can go to my website masonknowles.com and download articles and presentations that have the data. Look for SPF Industry Today and Tommorow. Also, send me an email and I will provide the report from ATI. You also be able to get it from SPFA.

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