Petromat is a polypropylene nonwoven needle-punched fabric which becomes an interlayer system when it is combined on site with an asphalt cement tack coat of approximately 0.25 gallon per square yard. The heat and pressure of an asphalt concrete overlay draws the asphalt cement tack coat up into the Petromat forming an asphalt saturated fabric interlayer.
To obtain full moisture barrier protection, the Petromat system is generally used over the entire width of a pavement. Petromat is extremely effective in new pavements.