Products / WeatherBond SureMB 70 SA Base Ply

A 70 mil, sand-surfaced, self-adhered SBS modified bitumen sheet on a fiberglass mat with a poly release liner, used as an air and vapor barrier, as a temporary roof for up to 90 days, and as the base ply in WeatherBond's multiple-ply systems under TPO AC Fleece or Fleece KEE HP set in Type III or IV asphalt or cold-applied adhesive. Rolls are 39 3/8 inches by 61 feet, about 78 lbs. The data bulletin says it is FM Approved and UL Approved when used as a vapor barrier and lists a water vapor permeance of 0.012 perms under ASTM E96.