Abstract: A waterproofing article in the form of rod-, or rope-shaped clay-containing compositions, and a method of waterproofing using the article, whereby a water-penetrable, degradable, or water-soluble film or coating forms an outer surface of the article for avoiding premature hydration of an underlying clay-containing composition. In the preferred embodiment, an inner core of a water-swellable clay-containing composition includes a coating of a water-removable or degradable material, completely encasing the major outer surfaces of the composition, having controlled, predetermined water-penetration; high pH degradability; or water-solubility so that the core of water-swellable clay-containing composition is quickly hydrated after water-penetration of the coating material, and to prevent clay hydration during installation, prior to water-penetration of the coating material.