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W = -t—[(0.0000036 in/in/°F) (288")(180°) + 0.06"] + 0.125"

Use a sealant joint at each column line.

In this calculation, 0.0000036 in/in/ °F is the coefficient of thermal expansion of brickwork, taken from page 36. 288" is the same as 24', the distance between joints. 180° is the maximum range of temperature that the brick facing will experience. This may seem large, but research has shown that dark-colored masonrv in summer j sunlight can easily reach 140°F, and winter nighttime temperatures in this region can go well below zero. The 0.06" is a calculated value for moisture expansion (page 77). 0.125" \s a Dimensional Tolerance for the brickwork, a relatively small amount, because we know the masons can easilv make small j dimensional adjustments in the head joints of mortar to maintain a constant width of expansion joint.

We apply the same formula to sizing the horizontal joint, the soft joint that must be provided below every shelf angle. The structural engineer wants to allow a full Vi" for deflection and creep in the concrete structure, and we include the same W tolerance:

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