Drainage systems for use in masonry block construction

A drainage system for use in concrete masonry unit (CMU) wall construction comprising:

• a masonry wall including a plurality of CMUs, each CMU including at least one cavity having a cavity width and an inside face adjacent an outside face of the masonry wall and the inside face defining a part of the at least one cavity;
• and
• an elongate flashing member wherein the flashing member has a width sufficient to extend from the outside face and past the inside face of the CMU but less than the entire cavity width, said flashing having a rear edge and a front edge;
• a layer of water permeable material attached to an upper surface of the flashing member, the layer of water permeable material including a plurality of longitudinally spaced apart transverse portions that extend toward the front edge of the flashing member;
• and
• a plurality of vertical blocks of water permeable material blocks positioned above the layer of water permeable material in contact with said transverse portions thereof, each of the blocks being positioned to extend upwardly into cavities of the CMUs, in use;
• the water permeable material of the layer and the vertical blocks having a porosity sufficient to permit water to pass therethrough but substantially insufficient to permit mortar and debris to pass therethrough so that water in cavities of CMUs drains through the transverse portions.