Vapor Proofing Mastic:
Mastic must have the following qualities:
Water Vapor Transmission Rate:
ASTM E 96
0.3 perms or lower
Stego Mastic by Stego Industries LLC
Construct pipe boots from vapor barrier material, pressure sensitive tape and/or mastic per manufacturer's instructions.
Ensure that subsoil is approved by Architect or Geotechnical Engineer.
Level and tamp or roll aggregate, sand or granular base.
Install vapor barrier in accordance with manufacturer's instructions and ASTM E 1643-98
Unroll vapor barrier with the longest dimension parallel with the direction of the concrete pour.
Lap vapor barrier over footings and/or seal to foundation walls.
Overlap joints 6 inches and seal with manufacturer's tape.
Seal all penetrations (including pipes) per manufacturer's instructions.
No penetration of the vapor barrier is allowed except for reinforcing steel and permanent utilities.
Repair damaged areas by cutting patches of vapor barrier, overlapping damaged area 6 inches and taping all four sides with tape.