Masonry Magazine October 1980 Page. 15
20 OZ. COPPER
PREMOULDED FOAM
NEOPRENE
EXTRUDED PLASTIC
Expansion Joint Fillers
FIG. 2
CONTINUOUS FLASHING
REGLET
FLASHING
SHELF ANGLE ANCHOR
WEEP HOLES
ELASTIC JOINT
SEALANT
COMPRESSIBLE MATERIAL
BELOW SHELF ANGLE
(OPTIONAL)
METAL STUDS
WIRE TIE
made to relieve excessive stress which might be expected to result from such movement. The movement of the brick veneer due to thermal and moisture expansion may be greater than the movement in solid or composite walls exposed to the same environment. This is due to the greater differences between the mean maximum and mean minimum temperatures of the brick veneer, and the absence of restraint usually provided by dead and live loads, masonry bonders or filled collar joints in solid walls. The isolated brick veneer will undergo maximum expansion and contraction due to thermal changes, and as a result, the number of expansion joints required will be increased. Special care must be exercised in design, detailing, and construction. For further information, see Technical Notes 18 Series.
Vertical Expansion Joints
Vertical Expansion Joints. Expansion joints in brick masonry oriented vertically are designed to accommodate potential horizontal movements in the masonry. The expansion joint must be fully compressible to permit the movement to occur without distress from excessive or concentrated stresses, see Fig. 2. Expansion joints must also be designed and located so as not to impair the integrity of the wall.
Parapet Walls
Parapet Walls-All vertical expansion joints should be carried through the parapet walls. Additional expansion joints through the parapet should be spaced approximately halfway between those running full height, unless the parapet is reinforced.
Horizontal Expansion Joints
Horizontal Expansion Joints. When the height of the veneer or the number and location of openings necessitates supporting the veneer on shelf angles attached to the structural frame, it is recommended that horizontal pressure-relieving joints be placed immediately beneath each angle, as shown in Fig. 3. This is particularly important in reinforced concrete frame buildings. Pressure-relieving joints may be constructed by either leaving an airspace, or by placing a fully compressible material under the shelf angle. In either case, the joint must be sealed with a permanent elastic sealant.
Steel Shelf Angles
FIG. 3
Horizontal Joint Reinforcement
Horizontal Joint Reinforcement. Horizontal joint reinforcement is not usually required in brick veneer since brick masonry is not subject to initial drying shrinkage stresses like concrete masonry. However, it may be beneficial to use limited amounts of horizontal joint reinforcement in the brick veneer to improve continuity at corners, offsets, or at intersecting walls. Single-wire horizontal joint reinforcement may be used to add integrity to the veneer in such places as corners. When using horizontal joint reinforcement it must be discontinuous at all movement joints. All joint reinforcement must be adequately protected from corrosion, see Technical Notes 11A.
Anchorage
Anchorage. When brick veneer is used to enclose skeleton frame structures, care must be taken to anchor the masonry veneer to the skeleton frame in a manner that will permit each to move freely, in-plane, relative to the other, see Fig. 4. Skeleton frames are more flexible than brick veneer and undergo greater deflections under load. The frame and enclosing veneer differ in their reaction to moisture and in the magnitude of the thermal movement. Where anchors tie the veneer to the structural frame to provide lateral support, they should be flexible, resisting tension and compression, but not shear. This flexibility permits in-plane differential movements between the frame and the veneer without cracking or distress. The flexible anchorage of brick veneer to skeleton frames, to permit differential movement of the veneer and frame, is discussed in Technical Notes 18 Series.
Shelf Angles
Shelf Angles. Where building codes or other factors do not permit the brick to be self-supporting for its full height, the veneer should be supported at each floor, or at least every other floor, by shelf angles as shown in Fig. 3. Care should be taken to insure proper anchorage and shimming of these angles to prevent de-
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