There are different kinds of outdoor build materials commonly used in both residential and commercial properties. Stucco is commonly used throughout the home. Stucco is a hard coat product used on the outside of the house due to it being both durable and having the ability to provide additional protection to the house. However, there is a similar material, known as Exterior Insulation and Finish Systems (EIFS), which is a softer synthetic, material that does not provide as much protection as stucco. If you’ve ever wondered what kind of material you have on the exterior of your house, here are a few ways you can identify each.
Three EIFS And Stucco Test Methods
The Installation Process
Stucco and EIFS are installed in two different ways. When installing stucco, a wire mesh is put into position first in
order to hold up the rock material. Once in place, the stucco is applied over the wire mesh. The wire mesh does help with moisture that moves behind the rock. On the other hand, EIFS uses a base board that is installed in the desired location. This board is often constructed from a Styrofoam. Once in place, a base coat is applied, followed by a finishing coat.
Both Stucco and EIFS can appear similar at first glance. However, while one is synthetic and the other is an actual layer of rock, there are some ways to identify differences. The synthetic design of EIFS will not allow water to pass through, either in liquid or vapor form, due to the solid nature of the material.
Stucco, on the other hand, is naturally porous. This allows some moisture to move both in and out of the wall. Essentially, it allows the stone to breathe. The pores can prove helpful in some climates, as fluctuation can prevent cracking.
Performing The Knock Test
If you did not install the material, you may still wonder whether or not you have stucco or EIFS. It can prove difficult to instantly identify one from the other by just looking at it. One of the best ways to test out the material is to perform what is known as the “Knock” test. Go outside and knock on the material. If it has a hollow sound, it likely is EIFS. This is because the sound travels through the Styrofoam base, hits the wall behind it and then reverberates back. With stucco, it should feel like knocking on stone. The entire stucco installation more or less is rock, so you can easily tell the difference with this knocking test.
Another way to test for stucco or EIFS is to check the gap. Often times at the base of the construction foundation there is a gap between the bottom of the stucco/EIFS and the ground. Feel the area under the stucco/EIFS. If you can feel cladding that comes out from the foundation close to an inch (or more) you probably have EIFS. When installing EIFS, the base board uses an extension system that is not always completely covered. With stucco, you do not have this.
Check Installation Points To Be Sure
If you are still not sure whether or not you have EIFS or stucco you should check installation points. Remove an outside light fixture, gutter trap, intercom or any other object that is installed into the wall in or around the stucco/EIFS. If you can see the Styrofoam board, you have EIFS. This will not be present in stucco (although you may see the edge of the wire mesh). By using these three different test methods, you should be able to identify whether or not you have stucco, or if EIFS has been used during the installation.
When looking to identify the difference between EIFS and stucco, you not only need to know what the difference is and what separates one from the other but, you also need to know how to identify the two from each other.