We purchased a 50 year old ranch style house and discovered that behind the exterior stucco is cinder block walls. The furring behind the drywall is only 3/4 inch thick with no insulation. Here in central Ohio we cannot keep it warm. I am thinking of removing the drywall from the perimiter walls and adding another 3/4 inch furring over the existing and re-drywalling with insulation. Is there an other less labor intensive way? Should I add a vapor barier and will a vapor barrier cause moisture and possible mildew inside behind the drywall?