Page 319 - Masonry and Concrete

Masonry Garden Walls

318 CHAPTER NINE

ALTERNATING ALTERNATING
COURSES COURSES

SMALL PILASTER LARGE PILASTER

FIGURE 9-4
Masonry wall pilasters.

of the wall, and larger pilasters to project on both sides (Figure 9-4).
The small pilasters are adequate for walls up to 4 ft. high, and the large
ones for walls up to 6 or 8 ft. high. Alternating courses of brick in the
wall must overlap the brick in the pilaster to form a strong interlock-
ing structure. If you live in an area that is subject to earthquakes, you
must use a special seismic design and will need the services of a struc-
tural engineer.
Brick walls are usually laid in a running bond pattern, and the two
3
wythes are tied together with 16-in.-diameter galvanized steel wire
Z-ties or corrugated sheet metal ties (Figure 9-5). Corrugated ties are
less expensive than the wire ties, but they have to be spaced closer
together, so more are needed. Most building codes require that rigid
1
wire ties support a maximum of 4- 2 sq. ft. of wall area and be spaced
a maximum of 24 in. on center vertically (every 9th course of brick) and
36 in. on center horizontally. Corrugated ties or flexible ties may sup-
2
port a maximum of 2- 3 sq. ft. of wall area and the spacing should be
reduced to a maximum of 16 in. on center vertically (every 6th course
of brick) and 24 in. on center horizontally. Every other row of ties
should be offset so that a staggered pattern is created (Figure 9-6). The
ties must be properly embedded, with mortar completely surrounding

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