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AIA Product Category Definitions


A needle-punched nonwoven fabric weighing a minimum of 4.1 oz. per square yard, which, when embedded in a field applied asphalt cement tack coat becomes an asphalt saturated fabric membrane. Properly installed it is a pavement moisture barrier and a stress absorbing interlayer which retards crack reflection and extends pavement life. It is then covered with an asphalt overlay or a surface maintenance treatment such as chip or cape seal. Paving fabric is millable and recyclable.

NOTE: It is recommended to stop milling above the system to retain the benefits of the waterproofing interlayer, or mill completely through the fabric elevation rather than mill exactly at the fabric interlayer.


A wet-formed nonwoven hybrid of fiberglass and polyester fibers constructed to a nominal 4.0 oz. per square yard dimensionally stable mat, engineered for use as an interlayer for asphalt paving. Paving mat is stable up to 495 degrees Fahrenheit to withstand elevated paving temperatures. When installed per manufacturers specifications in a field applied hot AC tack coat , the paving mat becomes an asphalt saturated membrane that provides an effective moisture barrier. In the pavement structure the paving mat provides low elongation, high immediate low strain tensile to retard crack reflection and extend pavement service life.  Paving mat is designed to mill easily and recycle completely.


Non Waterproofing Grid– A high modulus grid installed onto an existing pavement using a pressure sensitive adhesive on the grid or using a lightweight carrier fabric which is adhered to the pavement with an amount of asphalt cement tack coat that does not create a moisture barrier.  When the asphalt concrete overlay is placed over it, the grid embeds into and interacts with the overlay to provide tensile and torsional reinforcement to stabilize and strengthen the overlay. Grids are currently made in at least 2 different strengths.


Waterproofing Composite Grid– A composite of a high modulus grid and a paving fabric laminated in a manufacturing plant prior to shipment to the field. When installed, fabric side down over a field applied asphalt cement tack coat, the paving fabric side provides the moisture barrier and stress absorption functions while the grid top side imbeds into the asphalt concrete overlay to provide tensile and torsional reinforcement to stabilize and strengthen the overlay. Waterproofing Grids are currently made in at least two different strengths.


Medium Duty– A composite of a paving fabric, factory precoated with a rubberized asphalt cement with an adhesive additive to bond the membrane to the pavement.  Applied as strips over local pavement joints and cracks or full width on bridge decks, and then covered with asphalt concrete to provide the functions of moisture barrier and stress absorption. This system is also widely approved as a bridge deck membrane.

Heavy Duty– A composite of a paving fabric, a layer of asphalt cement with additives in the middle, and a layer of a high strength woven fabric.  The system is applied as strip treatment over an asphalt cement tack coat, paving fabric side down, on pavement joints and cracks under an asphalt concrete overlay to provide the functions of stress absorption, stress transfer, and moisture barrier.

Shingling” of all rigid interlayers required on horizontal curves.