A structure comprises at least one outer wall having an internal wall section and an outer wall section with an air flow passage therebetween. Air is passed through the air flow passage to inhibit moisture accumulation and/or mold growth. A controller may determines a parameter relating to condition of the air in the air passage and in response thereto control the air flow through the air passage. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.