Base sheets, useful in roofing applications and in other waterproofing applications, are described which comprise (a) a fabric layer having an upper surface and a lower surface, and (b) a coating of a coal tar enamel on at least one surface of the fabric, the coating having an exposed outer surface. In one embodiment, a parting agent such as sand is applied to the coated enamel exposed surface(s) to prevent blocking (sticking) of the base sheet when stacked or formed into a roll.