EIFS War Stories
This month's column contains a smattering of some of the more interesting EIFS situations I've run into over the years, with some ideas on what they mean.
Northern exposureI once got asked to figure out why some EIFS was coming off large, flat, jointless wall areas on a big commercial building in Michigan. It turned out that the foam was still well attached to the substrate but that the lamina was more than a little loose. It was hanging in 10-foot-high sheets like a gigantic curtain, from the top horizontal edge of the wall. At first, I though it might have to do with the migration of plasticizers from the reinforcing mesh. This was an unusual and rare condition that occurred in the 1980s when some improper coatings were used to protect the mesh. In essence, what happens is that the plastic coating that is on the mesh essentially liquefies and migrates through the basecoat and to the basecoat-foam interface. It then melts the foam. The lamina is then no longer supported, and thus is "loose." This failure did not have this characteristic appearance caused by bad mesh, so that was ruled out.
Over the years, I'd seen and heard a lot about foam melting due to heat. Obviously, this can occur during a fire but can also occur under normal conditions in certain odd situations. The melting occurs at the basecoat-foam interface. This makes the lamina loose. This can occur in small areas. For instance, due to a nearby hot barbecue, electrical transformers or any other things that get hot. The sun can also cause it. Standing there and staring at the wall, it took just a minute to realize the problem: The EIFS finish was dark gray, the wall was facing south and there was a large, greenhouse-type skylight with mirror glass on the low roof right below the affected area. The dark wall was getting a double dose of sunlight: the dark color, plus the reflections off the skylight.
The moral: Delamination due to dark colors and reflective surface can melt the foam in EPS-based systems, and even in northern climates.
What to do next time: When getting involved with the design of the building and with the selection of colors, check out the maximum allowable darkness of the EIFS finish's color with the EIFS manufacturer.
A way to fix it: Peel off the lamina, rasp the foam until it's flat and apply a whole new EIFS lamina-one that has a lighter color.
The tallest EIFS building?
A major A/E firm was designing a 60-story office building in Chicago. The building would take up an entire city block and was basically square in plan. It also had-get this-a cast-in-place concrete frame. This would make it one of the tallest concrete buildings in the world. This building was destined for fame. They also wanted to use EIFS because of its external insulation location, which allowed for significant economies in the concrete's reinforcing due to the building being so well insulated. They asked for technical assistance, as there were a myriad of engineering issues that had to be addressed.
The main building walls were also concrete and they wanted to cover the whole thing with EIFS. They also wanted to build a three-story-high square doughnut-shaped custom scaffold that would wrap around the whole building. It would be raised at the rate of one floor per week, as the floors were poured far above. The top level of the scaffold would install the insulation, the middle level the basecoat and the bottom level would do the finish. It's a slick concept. But they also wanted to be able to do this EIFS work year around.
Someone got smart and decided to go much further in the design phase into the EIFS contracting side of the story. So he sent the drawings to the few contractors in the area that could handle such a huge building.
The project was never done with EIFS. The problem was that no one would bid it. It was too big and too complex. In essence, too much risk. This was one of those rare mega-jobs where the contractor can either retire on it or end up sued.
The moral: Don't get too far into really large projects without getting all the possible parties involved. In other words, don't assume that just because it is a juicy big job doesn't mean that you don't need to get the basics sorted out first.
Heavy metal EIFSI once got a phone call from the agent of a well-known heavy metal music band. He said one of the band members was building a new house and wanted to have a guitar-shaped pool. The pool was to have six laser beams that go from the top to the bottom of the guitar, which look like guitar strings and would appear to vibrate due to ripples on the water. They also wanted to use EIFS as the interior surface of the pool wall and bottom, as well as on the walking surfaces at the pool's perimeter.
I told him that you do not want essentially naked people rubbing against our finish material. It was too abrasive and would hurt people. I also explained how it would not hold up well in a pool water environment. He understood and thanked me. A couple of weeks later, I got a couple of free albums (this was before CDs) of their awful music, as a thank you.
The moral: Sometimes customers have dumb ideas about what can be done with products but are smart enough to ask if it's really OK, before they do it.
Santa Fe, AlaskaObviously, there is no Santa Fe in Alaska but I met a self-made rich lady who thought so, at least from an architectural standpoint. This person had two jewelry businesses: one in Santa Fe, N.M., and the other on The Inside Passage of Alaska (where all the tourist ships go). She ran a store in Alaska during the summer and the rest of the year lived in Santa Fe. She had this pension for Santa Fe, adobe-style homes, and wanted one in Alaska. She wanted to make the adobe portions out of EIFS. In fact, this was more than a pipe dream; she actually built it. I got the call after it started falling apart.
The Inside Passage area is one of the rainiest on earth. It gets hundreds of inches a year. It basically does not stop for six months. Santa Fe, in complete contrast, is the highest major metro area in the United States, at about 7,200 feet. It's dry as a bone.
Her problems involved leaks. Who would have guessed? The problems were many, and included leaky windows, no caulking used, and one odd condition: rounded, adobe-style parapets. The large diameter radiuses of this type of adobe-style wall-roof transition detail are made to order for water sitting on them. On the flat top part, water just sits. On the slopes, it gets mildew in a huge way. And then the water just continues to run down the face of the wall, making the wall very dirty. The big problem, though, was the constant saturation of the EIFS lamina with moisture on the parapet's top surface. It had softened the EIFS lamina and water could percolate through it. From there, it got at the sheathing and wood, and showed up indoors.
The moral: Regional differences in architectural styles are often a reflection of the environment. Rainy places have sloped roofs and jungles have lots of ventilation, and so on. Be careful when looking at drawings for buildings of a style is not indigenous to where it is being built. Think about whether a certain roof or window or deck design would work at the location where the building would be built.
There once was a multi-story office building that was completely open to the outdoors on the ground floor; the ground floor was a covered car parking area. EIFS was used as a giant soffit on the underside of the second floor, thus keeping the pipes and floor warm, etc. A fire broke out in a parked car. The flames rose upward and came in contact with the EIFS. The heat immediately went through the EIFS lamina and melted the foam. The EIFS lamina was then no longer being help up by anything, and sagged and split open. Molten foam insulation then flowed out and the fire spread.
The moral: If wondering why it's not smart to use EIFS on a large soffit, this is a good one. If a "soffit" is small, like a large "return" at the head of a window, it will be attached somehow to the wall at the window, and also supported by the vertical EIFS above it. Thus it would be unlikely for such a small soffit to come apart in a fire. However, large continuous soffits, supported only at their perimeter, are quite a different story.
The moral of this article: In terms of using EIFS in ways that work, the trick is to be sure that what is proposed, in the way of product use, fits the capabilities of the product. In other words, is it close to what the product is supposed to be used for? In the end, it's not a matter of if you can sell it or if it will stay attached until the check clears, and so on, but rather if it will work.
EIFS manufacturers have staffs of technical people whose job it is to deal with EIFS issues. They deal with not just the routine inquires about typical uses of EIFS, but also about weird uses. Since they handle all sorts of bizarre product-use questions all the time, they should be viewed as a reservoir of information and experience at your disposal.