Page 158 - Masonry and Concrete

Masonry Construction Techniques
157
MASONRY CONSTRUCTION TECHNIQUES

ing leads. The poles attach to the structure at the corners or ends of
the wall, and the string line is pulled from pole to pole. The poles
must be rigid enough not to bend when the string is pulled taut from
one side, and they must be easily plumbed and maintained for the
height of the wall.
Brick masonry must be laid with full head and bed joints to assure
adequate strength and resistance to moisture penetration. Bed joints
should not be furrowed, but slightly beveled away from the cavity to
minimize mortar droppings in the cavity (Figure 5-20). Bed joint mor-
tar should be spread only a few feet at a time so that the mortar will not
dry out too much before the next course of units is placed. The ends of
the bricks should be fully buttered with mortar so that when they are
shoved into place, mortar is squeezed from the joint (Figure 5-21). So-
called clip joints in which only a thin section of mortar is placed at the
face of the joint will allow excessive moisture to penetrate the
masonry. Even though the joints look full and solid after the wall is
completed and much less mortar is required to complete the work,
callbacks from unhappy homeowners and the liability for water dam-
age and cracking make this a risky practice.

FIGURE 5-19

A masonry line block holds the string in place so units can be laid to the line.

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