Siga Majrex as ceiling air barrier
I have watched some build show videos where they have installed Siga Majrex onto the bottom of the ceiling joists and then added 2×4’s as firring strips perpendicular to the ceiling joists. So the Majrex was sandwiched between the ceiling joists and the firring strips.
2×4’s run perpendicular to the ceiling joists. Then they end up with drywall fastened to the firring strips.
This means the Majrex is 1.5” away from the drywall which means the Majrex is expected to support the full weight if the insulation. Does this work well in practice?
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