Page 274 - Masonry and Concrete

Masonry Veneer

273
MASONRY VENEER

Plastic tube weepholes are less conspicuous in the wall than open
joints, but they are also much less effective. The smaller drainage
capacity requires that spacing be reduced to 16 in. on center, and
much greater care in construction is also required to avoid blocking
the narrow tubes with mortar droppings (Figure 7-25). Cotton wick
weeps avoid the problems associated with plastic tubes but still pro-
vide better aesthetics than open joints. A length of cotton rope 10–12
in. long is placed in head joints at 16 in. on center, extending through
the veneer and up into the cavity well above the height of any possible
mortar droppings (Figure 7-26). The rope can be tacked to the backing
wall or adhered to it with a splash of mortar to keep it from falling over
during construction. After installation, the exposed portion of the

MORTAR DROPPINGS
EASILY BLOCK TUBE
DRAINAGE

WATER COLLECTS
BELOW TUBE

FIGURE 7-25
Plastic weep tubes are not recommended because they clog too easily. (from Beall,
Christine, Masonry Design and Detailing, 4th edition, McGraw-Hill, New York).

Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com)
Copyright © 2004 The McGraw-Hill Companies. All rights reserved.
Any use is subject to the Terms of Use as given at the website.