Page 416 - Construction Waterproofing Handbook

10.18 CHAPTER TEN
or dissimilar movement between these components. For
instance, joints between metal window frames and wall
facades provide a watertight transition between window
and wall components and allow thermal and differential
movement as shown in Figs. 10.18 and 10.19.
Sealants are often overused, especially in remedial
waterproofing repairs. Simply applying sealants over
failed areas will not adequately address failure prob-
lems. A thorough investigation or study should first be
completed to determine why materials or systems origi-
nally failed.
For example, sealants are often used in place of tuck-
pointing to correct mortar joints. This is a poor approach
if existing mortar is not of sufficient strength to maintain
envelope integrity. Such applications also allow three-
point adhesion and improper sealant depth, and under
structural movement sealant installation, repairs will
FIGURE 10.17 Dampproofing-to-flashing transition
detail. fail.

FIGURE 10.18 Sealant joints used for transition detailing. (Courtesy of Bonsal)