Icynene Moisture Problem in Cathedral Ceiling
Dear experts I am lost, please help!
I had Icynene light density foam sprayed under a brand new metal roof and the walls of the upper floor. That was in October 2011.
4″ in walls and 6″ between rafters.
It was all fine until now. Now it’s summer we have 36C, 32% RH outdoors right now at noon (June 21 2012), Location: Climate Zone 4.
At the peak of the cathedral ceiling inside it’s so damp that my glasses turn foggy.
To exclude the possibility of indoor moisture going up there I did the following experiment this morning:
I took a transparent plastic sheet/foil and covered a 1 sq foot area of the foam at the peak area. I put a thermometer inside the foil and one outside next to it.
I taped the foil air tight with 6″ of tape in all directions. There is no way air can get inside or behind the foil.
I started the experiment at 9:50AM this morning. Both thermometers show: 24C, 57% RH. Outside we had: 33C, 46% RH.
At 10:58AM, 25C 87%RH behind the plastic, 26C 69% in open space right next to it.
At 12:39, just 2.5hours later: we have 26C 99%RH behind the plastic foil and 27C 86%RH next to it in the open area. Outdoors: 36C, 32% RH
The absolute moisture per m^3 behind the plastic went from 12.3 grams/m^3 to 23.9gram/m^3
What’s going on here? Why is there so much moisture coming through the foam?
The ceiling feels like sauna at the top 5 ft. Obviously the moisture is not coming from lower levels since it’s all A/Ced and the above experiment excludes this possibility.
One more thing: the moisture clears up over night. When I go up there in the morning it’s 50% RH no problems. By noon it’s a sauna. And this cycle has been repeating for at least a month now.
I have a feeling that open cell foam is no good for our climate, despite all the marketing materials claiming otherwise.
Thank you for your help!
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