STRATAVENT® is a premium grade moisture resistant and flame retardant inorganic base sheet, asphalt coated on both sides and surfaced on one side with mineral granules with 5/8" perforations spaced 3" apart on center.

It's the granules on the bottom of the sheet that really make the venting system work, and the perforations that allow good attachment to the substrate without interfering with the venting. 

When asphalt is hot mopped on top of STRATAVENT^® Perforated, it flows through the holes and firmly bonds the STRATAVENT^® Base Sheet, and the subsequent plies, to the substrate with uniform spot attachment.

The granules on the underside of the STRATAVENT^® Base Sheet provide a consistent and uniform pattern for lateral movement of any trapped gasses, including moisture vapor.

UNIQUE IN THE INDUSTRY_____________________________

It's the unique design of STRATAVENT^® Perforated Membrane that allows STRATAVENT^® to be installed directly to GAFTEMP^® Isotherm insulation systems without requiring the installation of an overlay board between the insulation and the roofing membrane system.

As a venting base sheet STRATAVENT^® Perforated can be applied directly to an old smooth surfaced or spudded gravel surfaced built-up roof. The new roofing system is installed over the STRATAVENT^® membrane.

STRATAVENT^® Perforated can also be applied directly to an asphalt primed smooth structural concrete deck under built-up roofing system.