The Finish Line: Interesting Uses for EIFS
Industrial uses of EIFS
The good looks of EIFS aren’t in much demand when all the building owner is looking for is a basic cladding for industrial construction. What I am talking about is major industrial structures, such as steel mills and refineries. Usually, the cladding on such buildings is some form of sheet metal, often corrugated or ribbed in some way, or perhaps concrete. Sometimes, these buildings are completely non-insulated when first constructed but later get insulated as part of an energy saving program or a visual sprucing-up.
EIFS is normally attached to flat, smooth, continuous substrates but sometimes it can be connected to non-continuous substrates, like metal siding. Doing so takes some thinking to make sure it works. Whether or not this can be done depends on the spacing of the “hills” and “valleys,” and the width and shape of the “hills” (see drawing). For example, corrugated metal siding with closely spaced profiles can be used as the base for the EIFS foam insulation when mechanical fasteners are screwed directly onto the metal siding.
A better approach is to apply gypsum sheathing directly over the metal siding and then to glue the EIFS to the gypsum. The reason this is better is that the code requires a thermal barrier between the foam and interior, and sheet metal alone will not provide that barrier. Gypsum board will though; or you could spray a thermal barrier onto the inside face of the sheet metal, from the indoor side.
In industrial applications, be wary of site conditions that could affect the EIFS, such as high or low temperatures, chemicals in the air, high humidity, high voltages, and so on. To make sure the EIFS will perform, chat with the EIFS manufacturer and make sure that the EIFS will work in such an environment and on discontinuous substrates.
Almost every airplane hangar I’ve ever seen is a lightweight, long-span steel frame structure with metal siding on it. In some climate areas, hangars are heated and/or air-conditioned. Sometimes, existing hangars are upgraded by adding insulation. This is sometimes done on the inside using faced fiberglass but it can also be done from the outside with EIFS. There are a couple of tricks to doing this with EIFS, including those noted in the previous subhead.
The biggest single issue in this type of application is sometimes deflection, which is the distance that the supporting wall structure-metal siding over a metal structural frame-moves in-and-out when subjected to wind forces perpendicular to the wall. Deflection is usually expressed as a percentage of the distance between supporting framing, commonly called “l over some number,” such as l/240 etc.). For example, if the steel girts (framing) that support the metal siding are spaced at 5 feet (60 inches) on center, then, if the metal siding deflects 1/8 inch, the deflection would be ⅛/60 inch or 1/480 inch of the span.
With EIFS, there is a limit to how much flexing (deflection) the EIFS can withstand before it cracks. Compared to traditional stucco, EIFS is much more flexible and this helps allow its use on light, flexible structures, such as hangars and barns. When considering using EIFS over metal siding, be especially careful of buildings with aluminum siding, as aluminum is much less stiff than steel and can over-deflect. Aluminum is also softer than steel and extra fasteners may be needed for screws to get a good grip into the metal siding. The usual published limit for deflection with EIFS is around 1/240th of the span but the actual limit is greater. To make sure EIFS will work on such limber structures, do a little engineering homework first. Figuring out the deflection of metal siding is a basic engineering calculation and can be done by a structural engineer.
You may not be aware of this but Hollywood makes a lot of use with EIFS. This includes large-scale feature film sets, as well as stage productions, and Hollywood-related industries such as theme parks. I’ve had the good fortune of being involved with some of these faux building creations and it is an interesting experience to see how some of these structures are actually built.
The lightweight of EIFS and its ability to mimic other materials (especially stone) are the key draws to using EIFS. An example is a well-known recent war film involving a tumultuous amphibious assault. What looked like miles of bunkers on the coast were actually throwaway lightweight EIFS structures made to look like concrete. The EIFS “bunkers” were in the foreground and the in-the-distance images were not real, i.e., digital.
An extension of the “looks-real-to-me” approach to creating look-alike façade materials is in Las Vegas. Stroll down The Strip and look at the high-end newer casinos. What do you think that stone is made of on that European-themed goliath of a building? Even the casinos cannot afford real stone.
Here’s an odd one: In a downtown area, a series of row houses were taken down, leaving a number of side-by-side empty lots non-insulated old brick party walls. They cleared the ground and turned the lots into a parking lot. Then, to insulate the previous party walls, they covered them with EIFS. One was finished-off with a very smooth, bright white finish coat and was used as a movie screen to show films outdoors during the summer. EIFS was the perfect choice: seamless (good for a movie screen) and insulation to boot.
I had a related experience with the IMAX people. They were thinking of using EIFS indoors to make those special spherical screens used for their film productions. Normally, they use sheet metal or fabric but the seamlessness of EIFS appealed to them. The project got nixed due to code requirements for protecting the foam insulation from the occupied theatre space. Disney had the same idea but was thinking of using EIFS as a huge, seamless flat ceiling for a sprawling indoor downtown theme park. They wanted to project stars and airplanes onto the surface, like a movie picture screen. This concept got canned too, for the same reason as the IMAX jobs.
The combat zone
Law enforcement agencies have mock-ups of street scenes that look like movie sets that they use for training. Officers can practice defending themselves from assailants that pop-up at doorways or windows as they walk through the make-believe town, like in the film Magnum Force.
Due to its light weight and ability to look like various wall materials, EIFS and wood framing are sometimes used to make the façades. The building façades can be moved around with a forklift or crane to create different layouts, thus making different “towns.” When doing consulting for this bizarre application, I asked why they selected EIFS, as they use live ammo and the façades would get all chewed up by the bullets. They said they routinely patch the holes but the main reason is safety: the bullets go right through and don’t ricochet off. No EIFS producer I know makes reinforcing mesh strong enough to deflect a 9 mm round.
I’ve had a number of inquiries over the years about using EIFS as part of a solar heating system. The idea would be to build an EIFS wall at the proper angle to the sun, use a jet black finish coat and then somehow extract the heat off the EIFS lamina, and use that heat to keep a building warm as part of the heating system. There are some basic problems with this. First, is that to be efficient, the lamina would have to get really hot. A lamina that hot would melt the EPS foam. The second is that the lamina does not have enough heat storage capacity to pick up enough energy. Back to the drawing boards.
I did some work for the government on designs for portable structures for use in emergencies-like Katrina or an earthquake. These had to be all-climate, occupy-able buildings (sleeping rooms, kitchens, etc.), and had to be transportable by air in cargo planes or lifted into position by helicopters. EIFS was used on a number of prototypes and did well, especially due to its lightweight. EIFS worked especially well when we figured out how to build the wall framing within the EPS foam layer, thereby increasing by a few inches the usable space inside.
The mobile home industry got wind of this research project and tried to incorporate it in double-wide style truck-able houses. There were too many problems with production and aesthetics, so the market never went anywhere. There are, however, a few specialty companies that do make portable buildings with EIFS walls. They are used mostly for remote construction or research operations, like in the arctic or some impossible-to-get-to jungle area, etc.
Elevated temperature processes
Some industrial processes take place at elevated temperatures. There is a cost involved in maintaining these higher-than-normal temperatures and EIFS can help contain those costs. An example is the charming edifice everyone takes advantage of after-the-fact: the sewage treatment plant. Often these facilities consist of a series of large, round, covered, above-grade concrete tanks. Sometimes, the tanks are more than a story tall and a hundred feet or more in diameter. To work properly, the “stuff” in the tank must be kept warm. EIFS is a dead-ringer for insulating the tanks on the outside-simply apply the foam directly onto the concrete wall of the tank. The diameter of the tanks is often so large that the EIFS insulation can be applied as flat sheets without even curving or warping it.
The finish line
The message here is that EIFS isn’t just for motels and houses and strip shopping center façades. Keep your eyes open and you may find some unusual uses for EIFS that are not only interesting, but also profitable.