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Old 05-17-15, 08:22 PM   #6
stevehull
Steve Hull
 
Join Date: Dec 2012
Location: hilly, tree covered Arcadia, OK USA
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"Fiberglass" means a lot of things. Loose blown fiberglass, with no binder) can cause health issues, especially for the one installing it. I used a fiberglass blow in that was blown in with a resin binder. It does not compact, does not mold, is not friable and is not expensive. Netting was installed first, a slit cut and the material blown in. A slight roll to have it conform to the wall studs and that was it.

If the home is appropriately ventilated (thing ERV or HRV) then build up of toxic off gassing is a moot point (or very nearly so).

As AC correctly points out, you are in a mixed zone with both heating and cooling degree days. You are almost the same latitude as I am in central Oklahoma and a very similar heat/cool situation. Your issue is far more humidity in the summer than we have here.

The humidity issue is key as you have to decide where you put the vapor barrier. In far north (Madison, Fargo, Duluth, etc.) , the barrier is put on the warm side (underneath sheet rock), where in hot humid situations (like Miami, Houston, etc), you put the vapor barrier on the outside wall. The key is to prevent a critical dew point drop and condensation.

But a mixed climate is tough. In your humid situation, I would go for an insulation that does not degrade with moisture and has a barrier in it. For those reasons, I chose a resin impregnated loose blown fiberglass.

Think about R40 if you can . . . .

Not a perfect solution, but there is no "perfect" when it comes to insulating.

Steve
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