The new drainable EIFS feature a drainage plain that helps provide protection from moisture for the underlying materials.
Credit: Jameson Simpson
In 1996, a homeowner living in Wilmington, N.C., made a call to Daniel Bryson, an attorney based in nearby Raleigh. Bryson specializes in construction defects involving mass torts and class action lawsuits, but he had never heard a story like this one. “The homeowner was putting a new shutter on the garage. And he missed the shutter, and the nail went straight through the wall,” Bryson says. The man then broke open a piece of the exterior cladding and uncovered a horrific scene: the wood underneath had deteriorated from pervasive rot. “He thought he had stucco, but what he saw inside the wall he called Styrofoam,” Bryson says. “The building inspector had no idea what the product was. I had never seen anything like it.”
The house was actually wrapped in a proprietary lightweight synthetic cladding known as an Exterior Insulation and Finishing System (EIFS)—a multilayered wall system with thermal insulation built right in. It is composed of expanded polystyrene insulation board covered with glass fiber mesh and layers of thin synthetic coating for the exterior finish. Early system designs used an adhesive to bond the insulation board directly to the building’s sheathing. These systems, known as “barrier EIFS,” were touted for their insulation capacity and affordability. But what Bryson soon discovered was that they failed to drain moisture that got behind the finish coating of the system. “Water was getting in through windows and other wall penetrations, but the system had no way for the water to escape.”
Bryson filed one of the first EIFS lawsuits in the country and secured a settlement for his Wilmington client. He went on to win about $150 million in claims against EIFS manufacturers in the U.S., and was one of a handful of prominent attorneys in the 1990s who filed hundreds of lawsuits against the manufacturers for structural damage. Bryson and other lawyers dubbed barrier EIFS the ultimate roach motel: The water could get in, but it couldn’t get out. “The original iteration of this product was one of the worst I have ever seen in over 25 years of litigation, second only to Chinese drywall,” Bryson says.
Fast-forward to today. EIFS manufacturers such as Dryvit, Sto, and BASF have redesigned their products to include a drainage plane and a weather resistive barrier between the sheathing and insulation board. The drainage happens in one of two ways, most commonly through the use of vertically troweled mortar, which leaves adequate space for moisture to exit. Some systems specify drainage through a grooved composite board. These “drainable” versions of EIFS, first introduced in the U.S. around 1995, provide protection from moisture for the underlying materials. Bryson says that their introduction dried up the court cases: “The litigation has virtually disappeared.”
Joseph Lstiburek, principal of Boston-based Building Science Corporation and an ASHRAE fellow, was one of the first forensic engineers to sound the alarm over moisture buildup within barrier EIFS in the late 1980s. Lstiburek served as an expert witness for Bryson and became instrumental in the class-action lawsuits against EIFS manufacturers. Today, however, his assessment of EIFS has evolved: It’s “a phenomenal system,” he says. “They addressed the fundamental flaws that they had in the 1990s, which is they added moisture management. And now EIFS resembles the perfect wall.”
This October, when the U.S. Department of Energy strengthens regulations on energy efficiency for commercial buildings, some designers believe EIFS may become the best available cladding option. In an article published this winter in the trade magazine Walls & Ceiling, an architect named Chris Dixon wrote that “EIFS is positioned for a huge comeback in buildings in the United States.”
The EIFS industry hopes to finally shake the hangover of past litigation and become the comeback kid of cladding for both commercial and residential projects. In the meantime, the story of how this wall system evolved over the last four decades offers a valuable reminder for a building industry rushing to embrace ever-greater energy efficiency standards.
EIFS began as a pragmatic solution to a pervasive problem. After World War II, Europe needed to rebuild, and the system was invented to repair damaged masonry buildings. In 1969, Dryvit set up shop in Rhode Island and brought the technology to the United States. The American energy crises of the 1970s propelled more architects and developers to spec EIFS because it mimicked the look of stucco while providing something known as Continuous Insulation, or CI. Instead of placing insulation inside the wall cavity, which creates opportunities for thermal bridging, CI is wrapped around the exterior, creating an uninterrupted barrier. According to the EIFS Industry Members Association (EIMA), most EIFS systems use an insulation board with an R-value of R-5.6 per inch, which, when combined with traditional cavity insulation, can result in an overall value of R-16 or more.
When the EIFS problem surfaced in North Carolina in 1996, Tom Kenney, vice president of engineering and research at the National Association of Home Builders’ Home Innovation Research Labs, participated in a task force led by the Wilmington Buildings Codes Department. He spent a good portion of a year getting to the root causes of the issue and writing EIFS standards. He says the problem wasn’t solely with the EIFS walls, but with the entirety of a building’s construction. “The building codes back in the day were wholly inadequate with detailing the flashing systems that were necessary to keep water out of the walls,” Kenney says. “It really woke up the home building industry in general with regard to moisture management. It was a complete blindspot,” he says.
The Lido Beach Towers on Long Beach Island in New York, a structure that was re-clad in EIFS, survived Superstorm Sandy intact, despite the devastation of the property and the interiors.
In 2009, the International Code Council added drainable EIFS to the international commercial and residential building codes as acceptable for use. Current versions of the system feature advancements in the synthetic coating that enable EIFS to aesthetically mimic any finish—wood, stone, brick, even metal—at a fraction of the cost of the real thing. Moreover, the reinforcing mesh can be customized to climate and geography, offering things like increased impact resistance for hurricane-prone areas. Bob Dazel, AIA, marketing manager for strategic initiatives at Dryvit, says his company’s Outsulation product can withstand a small missile impact test; indeed, a hospital clad in impact-resistant EIFS won’t need to evacuate during a Category 4 hurricane.
David Boivin, CEO of Sto, points to the Lido Beach Towers on Long Beach Island as a good example of EIFS evolution. Five years ago the 1920s structure was re-clad in EIFS and after Superstorm Sandy destroyed several floors of the interior—depositing sand up to the ceiling of first floor units—the exterior survived. “Literally, the whole beach came up on that project, and the bottom floors were completely inundated with water and sand,” Boivin says. “When they cleared everything away, the EIFS wall structure suffered virtually no damage. The owners were stunned.”
Ryan Johnson, Assoc. AIA, of LSE Architects has worked on several hotel and casino projects that used EIFS. He says the insulation and the aesthetics make it a popular choice for commercial clients. “We’ve been trying to move the insulation to the outside of the building on all of our projects, no matter if it’s an EIFS project,” he says. But EIFS is the only option that offers true CI, he says: “Other product manufacturers aren’t figuring out how to attach their product back to the building without going through the exterior insulation. If it’s metal panel on the outside, and it’s got exterior insulation, you’re still punching little holes all through the insulation to attach it to the building.”
Today, EIFS manufacturers sell primarily to the commercial industry. Chances are you’ve seen the product, even if you didn’t realize what it was. Much of the Vegas Strip is covered in EIFS, including the Bellagio. Estimates give the system about 20 to 25 percent of the commercial cladding business. Dryvit, whose Outsulation product covers the Bellagio, has about 40 percent of the total market in the U.S. The company says that 95 percent of its business is commercial and 5 percent residential, which may reflect the stagnant residential market over the last few years, but mostly points to the residual reputation damage from past litigation. A look back at market share of EIFS usage shows an overall decline in the residential sector once the lawsuits hit. In 1998, EIFS was on the rise, with 4.7 percent of the market in new construction single-family and townhouses, according to the NAHB. In 2012, the residential market share for EIFS was 2 percent.
The challenge in rebuilding that residential market is dispelling leftover concerns among Realtors, insurance companies, and others who still malign the product even though the lawsuits are now well over a decade old. “I am perplexed why people would not want to use a system that is so flexible, so energy efficient, and so easy to apply, and extremely cost competitive to other wall claddings,” says David Johnston, the executive director of EIMA. “We need to move on.”
Nevertheless, Kenney hopes that some of the lessons born out of EIFS travails won’t be forgotten. The issues did spur building codes to evolve, he says, and ensured that “other cladding systems had a new awareness of that moisture management issue.”
Today, “as we ratchet up the energy codes, there are consequences,” Kenney says. What other building issues could emerge as the result of product innovation? “We’re in the midst of a sea change, and the marketplace is doing what it does best: innovation. But uncontrolled and unregulated, it can be the Wild West.”