Page 161 - Masonry and Concrete

Masonry Construction Techniques
160 CHAPTER FIVE

running bond, or stack bond with very little decorative pattern work.
Brick soldier and sailor courses create 8-in.-tall head joints. Because
the bed surface of some brick can be relatively smooth, mortar will
sometimes slump in a head joint of this height. Concrete block head
joints do not have the same problem because the block surface is usu-
ally rougher and holds the mortar in place better. Brick soldier and
sailor courses should be installed carefully to prevent voids in the
head joints, which might be easily penetrated by moisture. Units used
for sailor or shiner courses must be solid and uncored.
To achieve a consistent pattern on the wall, units with a pro-
nounced color range from light to dark, or blends which contain more
than one color of brick must be uniformly distributed. Brick manufac-
turers routinely attach instructions for unstacking and using each pal-
let of brick to assure that the colors are distributed uniformly in the
wall. Working from more than one pallet at a time will also help assure
good blending of slight inadvertent color differences. Narrow color
ranges, however, present fewer potential problems than wider ranges
or blends of more than one color (Figure 4-5).
Mortar color and joint type can be just as important in determining
the appearance of a wall as the selection of a unit type or color, and
variations in aesthetic effect can be achieved by using different types of
mortar joints. There are several types of joints common today (Figure
5-23). Rough-cut or flush joints are used when other finish materials,
such as stucco, gypsum board, or textured coatings, are to be applied
over the masonry. These joints are formed by simply slicing off excess
mortar with the edge of the trowel immediately after the units are laid.
Weathered joints are more difficult to form since they must be struck
off with the trowel point from below, but the mortar is somewhat com-
pacted by the action, and the joint sheds water naturally. Struck joints
are easily cut with a trowel point, but the small ledge created collects
water, snow, and ice, which may then penetrate the wall. Raked joints
are made by scraping out a portion of the mortar while it is still soft,
using a square-edged tool. Even though the mortar is slightly com-
pacted by this action, it is difficult to make the joint weather resistant,
and it is not recommended where driving rain, high winds, or freezing
are likely to occur. The cut of the joint does form a shadow and tends to
give the wall a darker appearance. Weeping joints leave excess mortar
protruding from the joint to give a rustic appearance, but again are not

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