All walls, floors, and slabs below grade shall be waterproofed by the application of mastic and fabric materials to the exterior of the wall, and beneath the wall and floor slab, with appropriate water stops at all other joints as shown in Koppers Bulletin AIA No. 12b, p23-p26 or the equivalent. If hydrostatic pressure is prevented by an adequate drainage system, such as outlined in Section 6-44, the walls need only be damp-proofed, as shown in Koppers Bulletin AIA No. 12B, p26 and 27 or the equivalent, and joints sealed with pitch without the need for an impervious membrane. (M.C. § 22.903(b); Ord. No. 0-64-29)