Copyright Goodheart-Willcox Co., Inc. 286 Section 4 Construction Details Code Note Wall Ties The International Residential Code (IRC) specifies that wall ties are not to be bent after being embedded in grout or mortar. Wire ties must be embedded at least 5/8″ into the bed joint from the air space. There must be at least a 5/8″ cover of mortar to the exposed face. Corrugated ties must penetrate to at least half the veneer thickness and have at least 5/8″ mortar cover. Ties should be placed so the portion within the bed joint is completely surrounded by the mortar. Flashing and Weep Holes Flashi ng and weep holes must be positioned above grade but as close to the bottom of the wall as possible. In addition, flashing and weep holes should be located as close as possible above open- ings and below sills. Locate weep holes in head joints directly above the flashing to ensure adequate drainage, Figure 14-13. Weep holes in which the mortar has been completely removed should be spaced no more than 24″ O.C. Weep holes in which wicking material has been used should be spaced at a maximum of 16″ O.C. When brick veneer is placed close to the base of the wall and under the flashing, the space between the brick and the backing needs to be filled with grout to the height of the flashing. This practice fills the void below the flashing so moisture does not collect under the flashing in the wall cavity. When installing flashing, attach it securely to the backing system and then extend through the brick face. The flashing should extend at least 8″ up the wall to ensure adequate moisture protection. Lintels, Sills, and Jambs Unless the masonry is self-supporting, brick veneer that is backed by wood or metal frame must be supported by lintels over openings. Loose steel, stone, or precast lintels should bear at least 4″ at each jamb. Space at the end of the lintel is required to allow for expansion. The clear span for 1/4″ thick steel angles varies between 5′ and 8′, based on the size of the angle selected and the rating of the steel. Concrete, cast stone, and stone lintels need to be the appropriate size in order to bear the weight of the veneer. Steel lintels with spans greater than 8′ may need lateral bracing for stability. Reinforced brick lintels can also be used. Expansion Joints Expansion joints may be needed to allow for horizontal movement. Expansion joints are required in brick veneer when there are long walls, walls with returns, or large openings. Composite Walls A composite wall is two wythes bonded together with masonry or wire ties. See Figure 14-16. The two wythes are joined together in a contin- uous mass using a vertical collar joint. A collar joint is the narrow space between the facing units and the backup units in a wall. See Figure 14-17. This joint prevents the passage of water through the wall. When building an 8″ composite wall, the first course of facing may be either headers, as shown in Figure 14-18, or stretchers. It is important that all facing courses be laid in a full mortar bed with the head joints filled completely. Mortar that is extruded (squeezed out) on the backside of the facing units should be cut flush with the trowel before it hardens. Goodheart-Willcox Publisher Figure 14-16. Composite walls can be bonded together with masonry or joint reinforcement. Joint Reinforcement Used to Tie Wythes Together Masonry Bond Used to Tie Wythes Together