EIFS Minimum Requirement For EPS Foam Thickness

Did you know there is a EIFS minimum requirement for EPS Foam thickness?

You may be under the EIFS minimum requirement for EPS Foam thickness because of an industry shift from 1 1/2″ foam to a 1″ foam standard. With the rising cost of material we have found that many Synthetic Stucco contractors are pushing 1″ foam. In years past the norm was an 1 1/2″ of foam. The problem with using one inch foam is that the minimum requirement for the EPS Foam is 3/4″ which one inch would seem fine then, but after sanding the foam it is getting close to the 3/4″ in troubled areas that need a little extra sanding, but that is not the real problem. The problem is that in many cases the design calls for aesthetic reveals or v-grooves, which are cut into the foam with a hot knife. These aesthetic reveals are anywhere from a 1/2″ to 3/4″ deep when using one inch foam. If you use one inch foam you are limited on your design because you cannot use the aesthetic reveals. The use of aesthetic reveals are great for stopping points when applying the EIFS finish coat so the entire area does not have to be done at once. Also, the aesthetic reveals allow for easy and cheaper repairs if the Synthetic Stucco becomes damaged down the road. Exterior Insulation and Finish System needs to re-finished from coast-to-coast to look brand new, otherwise you will be looking at a patch in the middle of a huge wall. Aesthetic reveals can add to the beautiful design of Synthetic Stucco, help the applicator when applying the finish coat, save costs on repairs. The cost savings of using 1″ foam is not worth the disadvantages and usually these savings are not passed down to the customer. Another disadvantage of using the thinner foam is the r-value you are losing. Your EPS Foam will be a 1/3 thinner so you will be decreasing your r-value of the Exterior Insulation and Finish System by that much. You will still be virtually  eliminating thermal bridging but for my buck I want to keep my r-value as high as possible. The technical term for what I have been calling ‘foam’ or ‘EPS Foam’ is expanded polystyrene (EPS).

There are places where you would use one inch Styrofoam. Window returns come to mind off the top of my head. Typically, the clearance around the window is much lower than the field wall. Door clearances have the same clearance issues. Also, one inch Styrofoam can be used in decorative trim applications

EIFS EPS Foam

EIFS minimum requirement for EPS Foam thickness

EIFS Preparations for Rough Openings Specification

EIFS Preparations for Rough Openings Specification

A complete overview of EIFS Preparations for Rough Openings Specification

 

In this post we are going to take a look at EIFS Preparations for Rough Openings Specification. Rough openings are normally thought of as door and  windows openings, but what also falls into this spec are expansion joints and the top of parapet walls. Dryvit’s Aqua Flash is applied to the jam. Read more EIFS Preparations for Rough Openings Specification

EIFS Sign Attachment Specification

EIFS Sign Attachment Specification

An overview of the EIFS Sign Attachment Specification

In this post we will take a look at the EIFS Sign Attachment Specification. It is not to often an EIFS guy will be there for the sign install, but I had to post this specification as almost every sign area that I am repairing has been installed wrong by the sign company, when it comes to installing over EIFS anyway. Read more EIFS Sign Attachment Specification

EIFS Horizontal Joint- Substrate Change Specification

EIFS Horizontal Joint- Substrate Change Specification

An overview of the EIFS Horizontal Joint- Substrate Change Specification

In this post we are going to take a look at the EIFS Horizontal Joint- Substrate Change Specification. In the field doing repairs we see cracking where there was no expansion joint between substrate changes. Read more EIFS Horizontal Joint- Substrate Change Specification

EIFS Inside / Outside Corners Specification

EIFS Inside / Outside Corners Specification

An overview of the EIFS Inside / Outside Corner Specification

In this post we will take a look at the EIFS inside / outside corner specification. The basic process of doing a corner is pretty much the same as a flat wall with a couple exceptions. Read more EIFS Inside / Outside Corners Specification

EIFS Termination at Parapet Specification

EIFS Termination at Parapet Specification

An overview of the EIFS Termination at Parapet Specification

In this post we are going to talk about the EIFS Termination at Parapet Specification. I have been doing EIFS for a long time and when we are out on repairs it seems like this is one of those things that is almost never done correctly. The proper way to terminate a parapet is to apply Dryvit’s Aqua Flash over the entire top of the parapet and down both sides at least 2″. Read more EIFS Termination at Parapet Specification

EIFS Grade Termination Specification

EIFS Grade Termination Specification

An overview of the EIFS Grade Termination Specification

In this post we will be taking a look at the EIFS Grade Termination Specification. Before we get into the grade termination spec it is understood that the substrate already has be treated with an EIFS approved moisture barrier (see the post . for more details on applying the moisture barrier). Read more EIFS Grade Termination Specification

EIFS Window Header Specification

EIFS Window Header Specification

An overview of the EIFS Window Header Specification

In this post we will take a look at the EIFS Window Header Specification. To properly address the window header when using EIFS a weep track needs to be installed at the head of the window. Note: the window rough opening first needs to be treated with the moisture barrier (refer to the post … for further details on applying the liquid moisture barrier to a rough opening). A metal window flashing is installed over the window head. The metal flashing is attached to the substrate and down over the window. The metal flashing should go up the substrate about 4″ and down over the window about a 1/2″. The EIFS approved weep track with drip edge is installed over the metal flashing. The weep track is installed about 3/4″ above the bottom inside corner of the metal flashing. This leaves a nice 3/4″ caulk joint between the metal flashing and the weep track. A rod of closed cell backer rod is placed in the 3/4″ joint between the metal and the track, and a bead of EIFS approved caulk (for more info on approved EIFS sealants, see the post EIFS Caulking and Sealants) is applied over the backer rod. The key with the caulk is not to allow it to cover the holes in the weep track.EIFS Window Header Specifications

 

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EIFS Window Header Specification