Ray Core Panels
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Hi,
These polyurethane panels have R values that are almost too good to be true. Does anyone have any experience with them or can anyone verify their claims?
thanks
Andy
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Replies
Andrea, I don't have direct experience with them but have researched them and agree that their R-value claims are not realistic. They appear to use the R-value of freshly installed foam, not that aged R-value, and they don't seem to include the inset studs in their calculations. If you search GBA you'll find that this question has been asked many times; here's one from 2010: https://www.greenbuildingadvisor.com/question/ray-core-walls.
There are different formulations of closed-cell foam that provide somewhat different R-values. The high R-value is due to the gasses called blowing agents that fill the foam's cells. Over time, air displaces those blowing agents and the R-value drops, eventually reaching that of still air, R-5.6/in. How long that takes varies but without a completely impervious covering on all sides, it will happen with all closed-cell foam.
Hi Andrea,
Thank you for considering RAY-CORE SIPs®. Yes, these claims have been verified. RAYCORE Structural Insulated Panels – SIPs are manufactured using the most advanced closed cell polyurethane foam on the market. All reported R-values are per 3rd party testing conducted on samples of RAYCORE manufactured product in UL certified labs. When comparing foams, it is very important that you remember that not all polyurethane foams are the same. There are thousands of different formulas of polyurethane foams out there, and application/production methods and the associated environmental conditions have a huge effect on the end results. In our 30 years of manufacturing structural insulated panels, RAYCORE has developed a manufacturing system that produces the highest quality product with the best R-value possible. Should you have any additional questions, please feel free to contact one of RAYCORE’s tech reps at 877.552.2440 or [email protected].
Robert Brusman, RAY-CORE SIPs®
Robert,
Links to your ESR and test conditions/reports would be helpful. Is the R-value calculated/tested based on the effective R-value of radiation at the foil surfaces?