Kneewall vapor retarder
I know similar questions have been asked previously, but I’ve hard a hard time determining which answer was right for my situation/climate. I have knee wall attic spaces on both sides of a dormer window. These walls currently have kraft faced R-19 batt insulation installed between 2×4 studs (with facing towards the interior), and I am planning to air seal these walls with foam board over the batts. A contractor mentioned using foam board with foil facing for a radiant barrier, but this seems that it would create a double vapor barrier with the faced insulation.
I live in the southeast in Zone 3. What would be the best option for installing an air barrier over the current insulation without causing moisture issues?
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