By Rob Fanjoy
The exterior insulation and finishing system has been around in Europe since the 1960s and first hit the United States in the early 1970s. When applied properly, it is an attractive finishing system similar to stucco that also doubles as an insulation system. When not applied properly, however, it can become a disaster, funneling moisture behind the finish where it can eat away a home from the wall sheathing in.
In the late '80s and '90s, horror stories and lawsuits abounded about homes finished with EIFS (also known as synthetic stucco) and the moisture problems that ensued, especially in the mid-Atlantic region around the Carolinas, where the system was very popular. While most of the repair work associated with EIFS is typically done by a specialty contractor, builders and remodelers who may have to work on an EIFS home would be well-advised to become familiar with the warning signs of moisture infiltration and damage.
Know what you're looking at
There are two main types of EIFS systems: barrier and drainable. Barrier systems are meant to resist water at the outer surface, but they do nothing with water that may get behind it. Drainable systems are applied over some sort of drainage plane and have weep holes at the bottom to allow moisture to drain away before it can do damage.
To find out what system you're working with, look for a metal or plastic edge with several holes in it (weep screen) at the bottom of exterior wall surfaces. If you see holes, it's a drainable system.
If you can't see the bottom edge for some reason, or if you're still not sure, the age of the house can be another clue. "Drainable systems didn't become readily available until around the year 2000, so EIFS homes built before then are typically barrier systems," says Tom Kenney, director of engineering services with the National Association of Home Builders Research Center (www.nahbrc.org).
Checking for damage
If you're renovating or adding on to an EIFS home, you'll want to know how to check for signs of damage. That's easy if you have to open up a wall or two during the demolition phase, but there are methods to check behind a closed wall, too.
"You can sometimes just poke an awl through the outer layer to make sure the system is solid," advises Tom. "It can give you a good sense of the condition of the sheathing behind the system, much the same way you might check wood members for termite damage."
More accurate methods include the use of scanning meters, which detect water in material through measuring changes in density. Metal probes can also be inserted into an EIFS system to more accurately measure moisture (readings over 20 percent usually mean moisture damage). However, meters can give false positive readings, and probes should be inserted in specific areas, so it might be wise to hire an experienced EIFS water intrusion inspector to perform these tests.
It is also wise to know the common areas of moisture intrusion with EIFS systems, so you'll know where to look for signs of damage or potential problems. Pay special attention to the following:
- Where roofs meet and terminate at a lower wall
- Chimneys, decks, dryer vents and other penetrations of the EIFS lamina
- Around doors, windows, gable vents and other "flashed" penetrations
- Anywhere that caulk is relied upon to seal between EIFS and other materials, such as window frames
- Through cracks in the material itself
Most experts recommend that EIFS homes be tested for elevated moisture levels at least once per year, using a combination of methods.
When to call a specialist
"Most contractors familiar with EIFS systems can handle minor to moderate repairs themselves," says Tom. "But you first want to be sure your insurance policy covers EIFS work, as many coverages exclude anything that has to do with EIFS."
The most common repair work usually entails many of the following details:
- Kick-out flashing at roof-wall intersections
- Removing old caulk and reapplying
- Recaulking around windows and doors, and making sure specially designed pan flashing is installed at the sill and where windows are mulled together
- Proper flashing of deck ledger boards
- Cap flashing, cricket flashing or kick-out flashing where applicable around chimneys
Tom warns that sometimes contractors can be fooled into thinking that a window's flashing or caulking could be the culprit in an EIFS leak, but what is actually leaking is the window itself at the jamb/sill connection. He also recommends that contractors closely read all manufacturer's specifications and recommendations when working with EIFS.
"Many manufacturers will only offer warranties and cover you if you use only their approved components as part of an entire EIFS system," says Tom. "Plus, they can often recommend the best repair components from other manufacturers."
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