Should closed spray foam be used in Cathedral vented roof?
We paid for spray foam, now the builder is saying there’s no need to spray as high in the cathedral roof, it would be more efficient to sheet rock near the HVAC and spray foam. After reading articles it says it’s best to spray un-vented cathedral roof, which will keep bad heat and air from entering at the surface, therefore the area between the HVAC and cathedral roof is cooler.
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