Drying out a wet dense-packed cellulose wall
What rules of thumb can I use for when a dense pack wall will dry out itself, and when insulation must be mechanically removed? Here in a 1938 stucco home.
The underlying cause was a pair of downspout nails installed in 1938, but angled somewhat downward. Chance are it leaked from the start, but maybe the rate went up as the nail rusted. In 2012 the wall was dense packed from the inside. Nothing remarkable appeared on an IR camera: that wall was looked at a month ago. Then last week, 77 years of paint peeled itself off the interior wall leaving baby smooth bare and slightly clammy plaster.
The house is painted stucco exterior, diagonal old growth sheathing, painted interior lathe and plaster. The diagonals mean that 5-6 stud bays could be involved, two have been exposed so far. The exposed two were full of inconsistently wet cellulose and completely wet sheathing. There seems to be no visible remaining paper on that exterior wall, but wood rot is fairly minor. The exterior stucco appears to be saturated (too wet to caulk to).
Presumably the relatively permeable wall dried itself for the first 75 years, but the addition of dense pack held water until the point of failure. The dense pack smells moldy (the stink is horrible).
Hopefully a few people in addition to Martin can weigh in?
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