Page 235 - Construction Waterproofing Handbook

4.10 CHAPTER FOUR

FIGURE 4.3 Proper flashing of window perimeter using
adhered waterproofing membrane applied directly over the
building wrap.

permits water entering near a window joint to travel directly into the interior rather than
being diverted back out to the exterior. Refer to Fig. 4.3 for proper detailing of this transition.
In fact, building paper is one such system, and it is widely available at most local build-
ing supply store and is installed easily (with exception of around the door and window
perimeters). It should be recommendation for use in all residential wood-frame construc-
tion. Not only do building wraps offer protection against water and moisture infiltration,
but they also add energy-savings benefits by eliminating much of the air currents entering
a home that can occur if no wrap is used beneath such installations as siding or brick fin-
ishes. When using a synthetic stucco system (EFIS), the manufacturer’s recommendations
should be referred to about the use of building wraps. Further, building wraps are not used
over block substrates when a stucco finish is to be applied directly to the block. However,
building wrap can be used as a damproofing system in cavity walls in most residential con-
struction. Figure 4.4 shows the proper application of building wrap with all seams sealed
to provide better protection against wind, water and insects infiltration.
When stucco is applied to block or plywood with lath substrates, special details are
required to ensure its effectiveness as a barrier waterproofing system. This will require an
elastomeric coating, as discussed in Chap. 3. While many builders avoid the use of true