Page 227 - Construction Waterproofing Handbook

4.2 CHAPTER FOUR
For example, there is never any coordination for transitioning heating and air-conditioning
components that may enter through the house’s facade. If anything is done, the transitions are
merely caulked to finish the installation, and usually an interior-grade painter’s caulk is used
rather than the exterior sealant recommended by the facade material manufacturer. If a flash-
ing were recommended for the junction, rarely would the contractor or subcontractor be aware
of its requirement, and usually only if the juncture between the components is unsightly
enough does the contractor finish the transition using caulking.
Unfortunately, local building codes ignore residential waterproofing requirements, as
do residential contractors. Codes do not mandate any requirements for the use of water-
proofing systems or proper transitioning for exterior systems. For example, even in
Florida, where hurricanes have led to high standards for individual door and window man-
ufacturing, the codes are essentially silent about the interface between the window and
door perimeters—the 1% of the building envelope that leads to 90% of all leakages,
including that during a hurricane.
And certainly inspections for sound waterproofing field practices are never employed
by residential code inspectors. This is true even for roofing installations. In fact, you will
never see a code inspector on a residential roof inspecting such simple requirements as the
transition between the roof shingles and plumbing stack pipe penetrations. Thus the home-
owner is left with the reality that waterproofing and related issues such as mold formation
are going to become maintenance issues rather than situations corrected or prevented dur-
ing construction.
It is interesting to note that the one residential construction exterior finish that offers the
most details about and manufacturer support for sound waterproofing principles during
construction is the exterior insulated finish systems (EIFSs), commonly referred to as
synthetic stucco systems. These systems became notorious for their leakage problems
years ago, and many local building enforcement agencies when as far as to ban the prod-
uct from use in residential construction. Unfortunately, these systems were demonized not
for their own inherent product failures but because of the thousands of problems caused by
not providing sufficient attention to the 90%/1% principle.
EIFSs had unique transition and termination requirements, and while the manufactur-
ers provided instructions and details to allow adequate installation of the product in resi-
dential construction, there were, of course, few homebuilders who paid any attention to
these requirements when it came to ensuring that the various subcontractors working on
the home’s envelope were adequately trained and equipped to install the transition and ter-
mination detailing necessary to ensure a waterproof result.
Soon the industry was besieged by problems, and following the 99% principle, even
though it was not the actual waterproofing system (EIFS) that failed but rather the termi-
nations and transitioning that were causing the water infiltration, the fact that the leakage
lead to wood rot, mold, and damage to interior finishes ultimately resulted in EIFSs being
banned for use in residential construction in many areas of the country.
This was occurring at the same time that the product was being used for the most part very
successfully in commercial construction. In fact, one cannot walk anywhere on the Las Vegas
strip and not be near a building using some kind of EIFS. The difference was merely in the
ability of commercial contractors to manage the installation process adequately, including
coordination among subcontractors for the terminations and transitioning of the EIFS. On the