Lightweight Nonwoven Geotextiles act as a permeable separation, allowing water to pass while preventing soils and other material from passing. Lightweight nonwoven geotextiles (3 oz. to 5 oz.) are used as filter fabric in subsurface drainage applications. Their high flow rates and small opening sizes make them ideal as filter fabrics. In addition to drainage, lightweight nonwoven geotextiles are often used as landscape fabric, weed barrier or for lightweight separation under pavers.