Out with the Old
But unlike many renovation stories in the news recently, the failed exterior product was wood and the product that replaced it was EIFS.
The four-unit upscale development overlooking Lake Washington was only 11 years old. But improper application of the wood siding and flashing led to the exterior’s quick demise, according to the architect in charge of the renovation, Jan Kofranek.
“Water got in between the wood cap on the railings—the horizontal piece—and the column itself because that joint was not flashed, or sealed,” he explains. “Also, the windows were not properly installed; they were not flashed at the hat. It was rotten to the point where you could put a screwdriver in the column and it would go all the way in.”
The association for the four 3,000-square-foot dwellings initially hired Kofranek to test and investigate the moisture situation. When Kofranek concluded the damage was severe, the association hired him to redesign and direct the restoration of the exterior.
Options availableThere was no choice for the first step of the renovation; the general contractor, McBride Construction, of Seattle, had to strip the building to the studs. Replacing the siding was a different matter. Kofranek could take another chance on wood or choose something else.
“We decided to put on the finish that would be watertight and more aesthetically pleasing and would require much lower maintenance, and that was the Dryvit,” he says.
Specifically, he chose the company’s new Outsulation Plus system, which he calls the Cadillac of EIF systems.
Michael Melandandri, residential sales manager for Evergreen Building Supply, the Dryvit distributor in the area, explains that the Outsulation Plus system was specially designed with moisture drainage in mind.
“What makes the system unique is the actual secondary moisture barrier that we use,” he says. “It’s not a paper product; it’s actually a liquid-applied moisture barrier.”
The barrier, which Dryvit calls Backstop, is trowel-applied over the sheathing—Dens-Glass Gold in the case of Highland House—which McBride Construction installed. Backstop is used in conjunction with grid tape, covering the sheathing board joints and flashing tape, which is installed over the rough openings such as windows, doors and air conditioning openings.
“That combination of our Backstop and the grid tape and the flashing is what provides that secondary line of protection,” says Barbara Catlow, manager of marketing services for Dryvit. “Outsulation Plus also incorporates an adhesive that is applied by a notched trowel in a vertical groove pattern and that vertical groove pattern provides drainage capability should incidental moisture get between the insulation board and the Backstop air barrier.”
The big pictureMelandandri says moisture drainage was only part of the picture with the Highland House project. Cooperation between installers of all the different products—including EIFS installer JJ Jefferson & Son—was key.
“The big benefit is having a secondary moisture barrier and the ability to drain any incidental moisture that gets in,” says Melandandri. “But what’s most important is that when we get involved in the project we can alert the builder and architect about details that have happened in the past.”
But given the controversy surrounding EIFS, wasn’t the building simply losing one risky product and gaining another?
“I happen to have had other good experiences with Dryvit in the past,” says Kofranek. “Like with any product or system it pretty much depends on the applicator, and we had a good applicator on the job, so I had confidence that it would come out all right.”
Melandandri says that as the past flaws in building practices are coming to light, Kofranek is one of a growing number of architects putting their trust back into EIFS, especially an EIFS product that can withstand the level of moisture constant in the Seattle area.
“I’d say it was rare before,” he says, “but with us telling architects the benefits of the system, they’re specifying it more.”
Kofranek says another reason he specified the Dryvit Outsulation Plus system was because it gave him the opportunity to create something of a sculptured look to the exterior. Although he was bound by the limits of the city of Kirkland, he projected certain elements of the façade and changed the entry canopy, along with making some other alterations.
“Considering that it was a very minor change in the form of the building, the results were pretty good,” he says. “It almost looks like a totally different building.”