01.030.0302A: Base of Wall Detail - Flashing, Drip Edge, Term. Bar, Movement Joints

This masonry base of wall detail shows a flexible thru-wall flashing mechanically fastened to the CMU backup through a termination bar, with a continuous bead of sealant along the top of the term. bar. The exposed portion of the flashing is a sheet metal drip edge secured held in place by mastic or sealant, with a hemmed edge, extending from the face of the masonry about 1/2″. The flashing has an 12″ (nominal) vertical leg, allowing it to extend beyond the top of the mortar dropping collection device. The wall has a 2″ clear air space for drainage, and weep vents are spaced at 24″ o.c. There is an air/moisture/vapor barrier on the cavity side of the CMU, and 2″ rigid insulation resides in the drainage cavity.  The concrete masonry backing has a vertical control joint, and the brick veneer has a vertical expansion joint.  Because the fluid-applied air barrier on the face of the CMU is not capable of spanning the width of the control joint (CJ), a self-adhering transition membrane of compatible material is applied over the CJ. The fluid-applied air barrier along with the transition strip provide continuity in the air barrier system.  The air barrier materials must not only be compatible with one another, but they should also be compatible with the flashing, and should be detailed for continuity throughout the building envelope, particularly at transitions and terminations.