I installed a 2 story fireplace with cultured/manufactured stone & later found that a vapor barrier should be used for interior, not just exterior applications as I initially misread it to be exterior only required.

Construction layers: Wood 2x4 studs >> 1/2" OSB >> Metal lathe >> Scratch coat mortar layer >> Mortared on cultured stone

Any concerns with this construction missing a vapor barrier on an instide application (house in NC). Thank you.