Attic with mold — spray foam solution?
Long description, so please bear with me:
House in Northern Illinois, built in 1962.
Major house fire in 2015…all but the attic and top floor bedroom/office were gutted and rebuilt in 2016.
Windows replaced with modern windows.
Doors replaced with modern doors.
Exposed insulation replaced with modern insulation.
Attic had 2 gable vents, a few pot vents and a humidity-and-temp controlled powered attic vent fan.
In 10+ years we never had any issues with mold.
When doing the rebuild, the old wood siding was replaced with vinyl and the gable vents were covered up (error by the siding company).
Fast forward to almost 2 years since the rebuild was finished.
Found major mold all over the attic (on the underside of the roof)..also major mold in 2 closets that adjoin the attic.
Mold is being re-mediated and I’m working with contractors to rebuild and re-insulate.
The gable vents were re-installed and a ridge vent was installed but the contractors both tell me that because my attic lacks soffit vents (because my house essentially lacks any soffits), they feel that the attic still isn’t getting ventilated enough due to how much tighter the house is now than when it was built in 1962.
They are proposing re-insulating the entire roof/attic space with spray foam and sealing off the gable vents/roof vents/power attic vent etc.
So..now to the questions:
Should I be looking at open or closed cell?
(open cell is going to cost me around 2.5K over what insurance will cover, closed cell will cost me around 7K over what insurance will cover)…I’ve heard so much debate on open vs closed…if closed is truly the better solution for my house I’d go with it..I just want to be sure…
Secondly….am I still going to have issues due to the house being tight (and I am going to either have humidity issues unless I spend a lot on some kind of ventilation system) or am I likely to be ok given that a 1962 house still wont be as tight as a modern-built one?
If it matters, I have forced-air hvac..no units or ductwork is located in the attic space.
Thank you…this is all so confusing.
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