A lot of us struggled to find Thermax and other such products last year, and rumors arose that it might be a discontinued product. I'm happy to report that is not the case.
I've connected with the proverbial horse's mouth at Dow, and I'm told Thermax and their other building insulation products are a growth business for them. Dow makes building insulation panels from polystyrene (not very suitable for yurts for several reasons) and polyiso (Thermax, Tuff-R, etc). Polyiso provides an R value of about 6/inch, polystyrene 5/inch. Polyiso accepts various facings (outer layers) while polystyrene facing choices are fewer. Polyiso is better for water resistance. Thermax is different from Tuff-R because the polyiso in Thermax contains fibers and other stuff that improves its fire resistance (how long it takes a fire to burn through a wall in a conventional building structure). In conventional structures, I am told you will die from the burning furniture, carpets, and other such materials long before fumes or flames from the Thermax or Tuff-R insulation in the wall - obviously Dow cannot speak to exposed yurt apps. In general, these products are sold through pro channels and bought by builders. They are not distributed very much through consumer/retail channels. Hence the lack at Home Despot, and I assume Dow's competitors sell mainly to builders as well. Different building insulation products are more/less popular in different states, and in different countries. Apparently in many places too many builders complained about the shiny aluminum in the sun, so non-reflective coatings are sold there instead. Thermax is not distributed very much west of the Rockies. Thermax HD which offers thicker aluminum facings that can withstand pressure washings in barns is not very popular/high volume at all, and quite expensive. Thermax HD is apparently fire rated for exposed interior use in barns. The aluminum is 4 mils thick and white coated on one side, 1.5 mils aluminum color on the other side, and no, even the thick side will not withstand a pencil, screwdriver, or even my fingernail (I am playing with sample squares now). There is another product called Thermax Sheathing that contains what appears to be even thicker aluminum facings, but still I can fingernail puncture it (my empirical test for longevity in routine use:) Dow also has a new product it is test marketing in a few cities that adds a structural layer to the polyiso to replace OSB below siding. It might be good for yurts because it is structurally strong compared to Thermax, although it is heavier and doesn't have aluminum facings/ radiant barriers which is a drag. It is 80% post-consumer waste by weight. And my fingernail won't penetrate the structural side of it. Anyway, I hope the above is useful. I also hope that well before Burning Man I'll nail down which is the best hexayurt material with Dow, and figure out how to make it available for some group buys through distribution. Cheers, Arthur --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "hexayurt" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/hexayurt?hl=en -~----------~----~----~----~------~----~------~--~---
