Synthetic
Stucco
The History of
Synthetic Stucco
Synthetic Stucco, also known as EIFS
(Exterior Insulated Finish System), was first used in Europe after the end of World War II. The product was first installed
on commercial buildings in Germany.
Synthetic stucco eventually made its
way over to the United States. As in Europe, the early installations were on commercial properties. In the 1980’s, architects
and builders began experimenting with the idea of using synthetic stucco on residential homes.
What is Synthetic Stucco?
Synthetic stucco installation begins with attaching 2’ X 4’ EPS foam panels to the plywood
sheathing of the structure. A fiberglass mesh is attached to the foam. The stucco, which is an acrylic, rubber based product,
is applied in one or two coats, and the final product is typically 1/16th to 1/8th inch thick. In comparison, hardcoat stucco
installed over wood strips, known as lath, or over metal lath, does not have the foam underlayment, and is usually 3/4"
to 1 inch thick.
Why Was Synthetic Stucco
Used?
The product was touted as the "Exterior
Cladding of the Future". Benefits included the ease and low cost to install. The EPS foam installed behind the stucco
provided additional insulation benefits. The finish color is consistent throughout the stucco, making it, in theory, low maintenance.
Architects favored the product because you could create interesting design features and details, adding to the curb appeal
of homes with synthetic stucco cladding.
What
are the problems with EIFS?
Synthetic stucco was meant
to be a barrier system, meaning it was not intended for water to get behind the stucco. Once water got behind the stucco,
the water was trapped, causing wood rot to the wood framing and sheathing of the home, as well as mold and mildew.
In the early 1990’s, problems were discovered on homes with EIFS located in Wilmington, North
Carolina. Removal of the stucco revealed extensive structural damage to the homes as a result of moisture intrusion behind
the stucco. Local building officials called in the builders, architects, and stucco manufacturers to evaluate the problem.
The examination of the home revealed moisture was intruding behind the stucco
cladding, as a result of poor design and installation. Installation defects include failure to install proper window, door,
and kick-out flashings, and leaking windows. In addition to the moisture related problems, it was discovered that the foam
behind the stucco, when installed at or below grade, was conductive to termite and fire ant infestation.
As a result of problems discovered with synthetic stucco clad homes, inspection and testing protocols
were created. The Exterior Design Institute, located in Virginia, was formed to educate and train independent, third party,
EIFS inspectors.
The Synthetic Stucco
Inspection
A moisture intrusion inspection on a home
with synthetic stucco is a combination of a visual inspection, and moisture detection using moisture meters designed specifically
for this purpose.
The visual inspection accesses the installation of the
stucco. The inspector verifies whether flashings are properly installed. The stucco is checked for any signs of damage, cracking,
and delaminating. The inspector will determine if the stucco system terminates above or below grade. The windows and doors,
porches and decks, and utility penetrations are carefully examined.
The
home is then scanned for moisture using a non-invasive meter, typically a Tramex Wet Wall Scanner. This type of meter will
scan up to 3 inches behind the stucco for any signs of moisture. The drawback to this type of meter is that false positives
may occur as a result of metal installed behind the stucco, such as metal studs, electrical wiring, and plumbing piping. Inspection
protocols require that specific areas be tested using a probe meter. With permission from the homeowner, two holes are drilled
in each probe location. The probe meter will provide readings of the actual moisture content of the sheathing behind the stucco.
Moisture readings below 14% are considered low, between 14 and 18% medium, and readings above 18% high. Moisture levels above
25% for an extended period are conducive to rot to the wood framing and sheathing, as well as mold and mildew.
All readings are recorded, and digital color photos are taken to document the condition of the system,
including components installed correctly and incorrectly. A computer report is compiled from this data.
Why is it important that my stucco inspector not do any repair work?
If you interested in obtaining a Stucco Warranty, All
Stucco and Mold Inspections follows the inspection protocol of the nation’s largest stucco insurer and our
reports are accepted for review and possible warranty coverage. With this solution you can feel safe that
your warranty company will not disappear, you can feel secure that your interim and post repair inspections will be through
and honest. Warranties are written by Moisture Warranty Corporation.