Section 385-890-C-IV - Ground Moisture ControlA.Vapor RetarderIf the space under the home is to be enclosed with skirting or other materials, a vapor retarder must be installed to cover the ground under the home.
B.Vapor Retarder MaterialA minimum of six mil polyethylene sheeting or its equivalent must be used.
C.Proper Installation1. The entire area under the home must be covered with the vapor retarder as noted in Paragraph A of this section, except for areas under open porches, decks, and recessed entries. Joints in the vapor retarder must be overlapped at least 12 inches.2. The vapor retarder may be placed directly beneath footings, or otherwise installed around or over footings placed at grade, and around anchors or other obstructions.3. Any voids or tears in the vapor retarder must be repaired.At least one repair method must be provided in the manufacturer's installation instructions.02-385 C.M.R. ch. 890, § C-IV