All medium density spray polyurethane foam is an air barrier material at the minimum installed thickness allowed of 12mm. An air barrier assembly must meet all the requirements outlined in the local Building Code. To do so, other materials must be used to "transition" to penetrations and to terminate. Normally a sheet membrane is installed at these transition points then sprayed over. With a declared and tested assembly, spray polyurethane foam provides all the requirements for an air barrier as required by Building Codes.