Re: Insulation/vapor barrier on cinder block home in Florida
The problem being encountered here is not interior generated moisture, but moisture that is being driven through the exterior walls where it encounters a cold, impermeable air barrier on the inside. Here it condensates. This type of problem did not exist before the advent of air-conditioned homes and the use of absolute air barriers such as plastic. Those interior walls must let the moisture continue on through. Similarly, wall papers with plastic coatings or metalic finishes should not be used on exterior wall surfaces as they also form impermeable barriers.
In hot humid climates, if a vapor barrier is to be used at all, it should be on the exterior side of the wall, the opposite of in Northern climates. An absolute vapor barrier such as sheet plastic should not be used at all in either climate. My house here in Portland ,Oregon does have such a plastic barrier in back of the drywall. However, the air in Portland in summer is very low in humidity. Also, air-conditioning is not used here as much as in other parts of the country, so condensation inside the wall is not a problem.