Brian, yeah, I see how that

Brian, yeah, I see how that could happen, especially since there’s some overlap in the USDA and IECC climate zone numbers there.  There would be no confusion in a place like Florida, though, where the IECC climate zones are 1 and 2 and the USDA zones range from 8 to 11. 

Thanks Allison, but I’m also
Thanks Allison, but I’m also familiar with the building version of climate zones. What made me believe that Daniel was addressing the agricultural system was his reference to the actual temperature in his area. As far as I’ve seen there’s no specific temperatures embodied in the building climate system, only broad areas most likely tied to heating degree days, average annual precipitation, etc.

Sorry, my previous reply was
Sorry, my previous reply was intended for Brian, not Daniel 🙂

No need to search online,

No need to search online, Brian.  I wrote about the International Energy Conservaton Code (IECC) climate zones here:

Do You Know Your Building Science Climate Zone?

@Daniel, around these parts,
@Daniel, around these parts, any reference to climate zones means IECC Climate Zones (google it), which are ‘backwards’ from USDA climate zones… Z1 includes the southern tip of Florida, Z7 includes northern Minnesota.

If your outdoor temperature
If your outdoor temperature dropped below -10F then you are in zone 5 according to USDA. Even for one night. Here in Vermont we were heading to a year (2019)in zone 7 , but a couple sub zero’s (single digits) have put us in zone 6. Of course the maps most garden catalogs use are never updated, so they mostly have us in zone 4

My suspicion would be a mold
My suspicion would be a mold issue. I would look into that.

We were told to put open cell
We were told to put open cell foam on our roof deck in our main attic, as it was not venting well and causing ice daming. We now have an off gassing issue (sweet chemical smell, or burnt coffee type of smell) with the foam when it is humid outside or too humid inside. We have also just discovered that the few spots we have cut out show it is not adhering to the deck and has a 1 inch gap where you can feel cold air moving behind the foam. We also found out that the installer did not make the entire attic monolithic, only about 50% of the attic where we had no floor boards did he make the foam come down far enough, so we have air infiltration there. He also told us to leave the old blown in insulation that was under the floor boards in the attic to leave in place. We do have a hard time getting the humidity under control in the house. We have a 100 year old home that has also been added on to. We have the foam in many of the walls too, in the crawl space(where it is also off gassing) and in 2 other attics in the house. We have an ERV, dehumidifier, humidifier, 2 ac units, 2 furnaces which are forced hot air. One set is in the attic, one set is in the finished basement. The humidity in the house can quickly go from bieng too dry when humidifier set low with the wood cracking to the windows dripping with water when set a little higher. Trying to decide if we need to rip out the open cell foam and start over or if we should try to fix the problems with the foam. It is a large house and attic, so none of this is cheap to do. Any and all adivce would be appreciated. Installer and manufacturer are being horrible about the problem and not wanting to help. We just want to solve the problem.