Quick question I hope. We are in a Zone 3/4, northern Maine. Existing 2x4 build house - renovation. We want to do a Mooney wall... another 2x4 wall basically (not 2x2) but we cannot get blown insulation out here. We can get Rockwool. Never used it before. It is said that Rockwool doesn't need a vapor barrier. So... do we need a vapor barrior for a mooney wall built with rockwool insulation? Nothing? Add some sort of vapor barrier just before putting sheet rock up? Or special ?? paint on the sheetrock? (Outside is wood plank topped with Hardie cementitious lap siding.) Thank you. (And meanwhile, I'll cruise the Mooney wall posts here on the forum some more.