Copyright Goodheart-Willcox Co., Inc. 246 Section 4 Techniques ■ ■ Flashing. Flashing materials should be stored where they will not be punctured or damaged. Plastic and asphalt-coated flashing materials should not be stored in areas exposed to sunlight. Sunlight causes them to become brittle. ■ ■ Insulation. Rigid insulation should be stored where it is not exposed to sunlight. Sunlight over time can cause rigid insulation to deteriorate. If rigid insulation is stored outside, it should be off the ground, covered, weighted down, and protected because the lightweight panels are easily damaged. Protection of Walls Masonry walls that are exposed to heavy rain dur- ing construction can become so saturated with water that they may require weeks or even months to dry out. This increases the likelihood of soluble salts going into solution, which may contribute to efflorescence or contaminate other elements of the structure, such as concrete, plaster, and trim. All walls should be kept dry by covering the top of the wall with a strong, water-resistant membrane at the end of each working day. The membrane should overhang the wall by at least 24″ on each side and be secured against wind. The cavity wall should remain covered until it is completed and protected by other materials. It is important to keep masonry from freezing while the mortar is setting or when new material is to be placed on previously laid units. Mortar joints are sus- ceptible to freezing. If freezing occurs, the bonding between the units is affected and damage may occur. There are many ways to protect newly laid masonry when freezing temperatures are forecasted. Using insu- lated blankets or erecting shelters are two methods to keep mortar from freezing. To cover masonry, drape blankets over the newly laid units. Place bricks or 2 × 4 lumber as weight on top of the blankets to reduce the chances that wind will move the blankets. Where one blanket ends and another begins, overlap the seams and place the weight, such as a number of bricks or a concrete block, against the blankets to secure them against the wall. 12.3.8 Laying a 10″ Brick Cavity Wall with Metal Ties A typical 10″ brick cavity wall with a corner is shown in Figure 12-60. Use the standard planning and layout procedure in laying out this practice wall. Flashing has purposely been omitted in this exercise. Be especially careful not to drop mortar into the cavity. P R O C E D U R E Laying a 10″ Brick Cavity Wall with Metal Ties 1. Locate the outside wall edges and snap a chalk line to preserve the location. 2. Lay out the brick dry to determine proper spacing and any layout problems. Locate the inside line for the backing wythe such that it is 10″ away from the outside wall edge. This should form a 2″ cavity between the wythes. 3. Lay the inside bed course beginning at brick #1 and continuing to brick #2. Work from both ends toward the middle. Use a full bed joint, checking the bricks to be sure they are plumb and level. Use the chalk line to ensure a straight wall. 4. Continue the outside wythe by laying brick #6 and the closure between brick #6 and brick #1. Level, align, and plumb this part of the wall. Check to be sure the corner is square. 5. Bricks #3, #4, and #5 are three-quarter brick. Cut them. 6. Lay bed bricks #3, #4, and #5 in the position shown in Figure 12-60. Level and plumb the brick. Be sure the outside edge of bricks #3 and #4 are 10″ from the inside face. Check the position of bricks #2 and #5 to be sure they are square. 7. Lay the brick between bed bricks #4 and #5 and finish the leg from bed brick #3. Level, align, and plumb these sections of the wall. The first course is now complete and should be square at the corners and 10″ wide throughout. 8. If you did not use empty head joints for the four weep holes shown in the elevation, open those joints or insert tubing or wicking at the weep hole locations. 9. Cut three (3) three-quarter bricks for the second course and lay the mortar bed for the second course. Bevel the mortar bed to avoid dropping mortar into the cavity. 10. Lay three-quarter brick #7 at the right end of the wall over bed bricks #2 and #5. 11. Lay second course brick #8 at the other end of the wall and complete the wythe between them. 12. Complete the second course following the procedure established for the first course. Plaster back any mortar that is squeezed out of the inside bed joints. Keep the cavity clean. 13. Locate the four metal Z-shaped ties as shown in the second course plan. Embed the ties in the mortar bed being sure that the drip on the metal ties points downward if your ties are of this design. 14. Build corner leads six courses high on each end of the wall so a mason’s line can be used to aid in the construction of the wall.