Finish Line: What Not to do With EIFS
On retrofit projects, perhaps in an effort to avoid removing and reinstalling existing downspouts or on new buildings to hide them, I've seen downspouts buried inside the EIFS foam layer. Doing so is easy-just remove some of the foam to accommodate the pipe and install the foam over the pipe. The first time I ran into this dumb idea was while investigating a leaky wall. Well, I guess you could say that the wall itself was leaking and it turn out that the downspout had gotten plugged and was overflowing at the seams between the pipe sections. The moral to this is that rainwater belongs outside of the wall and to fix this, the wall needs to be torn apart.
EIFS with drainage-as gutters.
Somehow, some designers have gotten the dumb idea that the drainage plane on EIFS with drainage, the one between the foam and the water barrier, can be used as the primary conduit-a gutter if you like-to route water leaks (say from windows) back to the outdoors. In other words, rather than using flashings and other sealing materials to capture and direct the leak water at its source to the nearest place outdoors, such as occurs at a window sill, the water is permitted to be dumped into the EIFS drainage cavity.
From that point, the water is allegedly supposed to work its way harmlessly downward (in some cases several floors) and finally back outdoors. It doesn't work that way. Some water remains in the wall and meanwhile the insulation gets damp and the water barrier is damaged. The moral: The drainage portion of EIFS with drainage is intended and only really functions to provide a path for incidental moisture that it's getting through the field of the EIFS, say due to a breach in the lamina due to impact damage.
EIFS as large indoor ceilings.
I was once involved with a huge project overseas where they wanted to have an indoor theme park with an expansive (a whole city block) seamless ceiling. The idea was that they would project images on the ceiling (like stars at night and airplanes flying). EIFS would seam ideal, as it's lightweight and could be installed without joints. The problem is that during a fire, the foam would melt, sending liquid plastic resin down on top of people. The moral is that this is why the codes require that indoor uses of foam plastic be protected with a 15-minute fire-rated material, such as drywall; the EIFS lamina does not provide the required fire rating.
EIFS as a beach.
A rock star contacted me once about lining the inside of his swimming pool and the concrete apron around it with EIFS finish. He said it looked like sand to him. I explained that if he did line the pool with EIFS finish, his "I'm-with-the-band" groupies would be de-skinned as if swimming through coral. Also, the EIFS finish cannot stand the chorine in the pool water. Moral: If you do not see an unusual use of EIFS in an EIFS producer's catalog, you better ask first to see if it will work. Luckily this guy did.
EIFS for traction.
I've seen this odd use of EIFS finish actually done a few times, usually with leftover material. The idea is to make concrete walkways less slick by applying the gritty EIFS finish to the concrete. It does work-for a while. The weather and sun, and perhaps de-icing salts, ruin the finish in a season or two. By the way, there are numerous products that are specifically for this purpose but they are chemically different than EIFS.
Wrap-around EIFS parapet panels.
Sometimes, parapets extend up past the edge of the roof, thus hiding the roof and whatever it's on. Possibly, the top panel can be made of a prefab EIFS panel wall with the outside face, the top edge and the inside face all done in EIFS at the panel plant. Thus, once the panel is up, the inside is ready for the roof edge. If you don't use a parapet flashing, this can look really nice by having no "trim" at the top.
The problem is that the sealant joints-that run vertically between panels-go up, over and back down the inside at the top of the panel. This joint, especially on the top edge, gets really severe weather and sun exposure, and if the sealant is the only thing that is present to keep water out, it will leak. And keep in mind that the interior of the sealant joint is essentially a vertical shaft that would allow water to immediately travel downward, probably arriving indoors at the window head of the most deluxe office at the top of the building. The moral is that a parapet flashing must be used.
EIFS as foundation insulation.
First, in many areas the codes simply do not allow EIFS to be used below grade. Some codes require EIFS to be held 6 to 8 inches above finished grade. The real problem is that EIFS does not hold up well underground and if counted on to keep water out of the basement, it probably will not do so, even in places where the soil is dry. The moral is to use an insulation system that is intended for use with foundations, not an above-grade vertical wall material, such as EIFS.
I got involved with a Hollywood production that involved WWII beach landings. There were supposed to be bunkers (pill boxes and gun emplacements, etc.) on the beach but the location had none, so bunkers had to be built. The bunkers were made of very light framing with thin foam and basecoat only (no finish). Basecoat without finish looks a lot like concrete, so it was very hard to tell that the emplacements were not really what they were supposed to resemble. The bunkers were bulldozed after the filming, as they were unstable and fragile. The moral: If a building is supposed to look like a bunker, an EIFS finish should be used on top of the basecoat to give the lamina extra protection.
With the advent of computer-controlled foam-cutting machinery, it's possible to produce very large foam shapes to exacting tolerances. This is how the hull shapes used to produce fiberglass boats are sometimes made (and sometimes prototypes for new car bodies). An aviator contacted me. He was building his own plane and wanted to use an EPS core for the fuselage and wings, and then cover it with basecoat and finish. I explained what epoxy and carbon fiber is used for and that EIFS is not a structural material. He gave up, probably because he would be flying it. The moral: Buildings aren't intended to fly.
An odd EIFS application that does work.
I once attended an outdoor summer showing of "King Kong." A projector and speakers were set up in a field and the image projected on the wall of what was mostly an old brick building. Kong literally climbed up the wall. It was cool. The wall on which the image was projected was not brick but this "screen wall" was bright white and seamless. The screen was EIFS, with a very smooth finish. So the building owner got some extra insulation and the locals got a nice screen.
If sun energy is used to heat water, one way to do so is to make a shallow box with glass on one side. Inside the block is a black plate, backed up with insulation. The box faces the sun and water trickles down in the black surface and warms up. It is then collected and used for heating.
An architect called me and wanted to use EIFS as the collection medium-the black surface and the foam insulation. It took a few minutes of math calculations to determine that the heat would melt the foam. So, the idea was abandoned in terms of already-worked-out commercial designs that use the same basic concept. The moral: There's no telling who will dream up ideas for EIFS. This architect turned out to be one of my classmates from college, who happened to mention while we were chatting, "I had this architect friend in college named Rob Thomas ...." Small world.
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