The installer wasn t reading his foam correctly.
Closed cell foam attic insulation problems.
We have some evidence from the field that that s not it and if it were the problem closed cell spray foam would rot out the osb even faster.
In an unvented attic scenario to limit air leakage as well as any associated condensation at the roof line a continuous air barrier is required.
It is the best for mold prevention.
Poor application of the spray foam insulation.
It was actually curing out and making foam before it could adhere to the wood.
The problem you saw with the closed cell foam pulling away like that is due to the heat of the foam was to hot.
It is not however the first solution.
Nothing unusual about that.
Choosing a closed cell spray foam insulation can reduce the noise pollution that exists outside while adding strength to your overall structure.
Moisture from the attic another possiblity is that the moisture is infiltrating into the attic from outdoors.
The american lung association also recommends it for a different reason.
Choose open cell spray foam when insulating roofs since closed cell foam can trap water from a leaking roof damaging the framing material and roof sheathing.
That makes the surface of the spray foam cooler possibly even below the dew point.
Insulating with spray foam insulation at the roof line will cause moisture problems with the roof sheathing.
The attic is much warmer than outdoors in winter but significantly cooler than the living space if you leave the old insulation in the attic floor.
Removing the attic floor insulation will solve this problem.
A lot of builders and homeowners are going with spray foam insulation because of the airtightness benefits but then the questioner mentioned that the spray foam contractor had intentionally left big holes to the outside by not sealing the gable vents.
Earlier this year i got a question about a home that had spray foam insulation in the attic.
The poor application of spray foam insulation by an untrained or unlicensed contractor can lead to several problems according to fine home building.
Over time trapped moisture can cause serious problems.
He should of stopped and turned down the heat on his hose temp.
It is possible for spray foam to add up to 250 racking strength to your roof or walls when the product receives a correct installation.