Installer Training Series, Video

BuildBlock ICF Installer Training Series: ICF Plumbing, Electrical, and Mechanical Installation

ICF Plumbing, Electrical, and Mechanical Installation

Welcome to the BuildBlock ICF Installer Training Series: ICF Plumbing, Electrical, and Mechanical Installation. This 20 part video series is intended to be an educational walk through of the ICF building process. From the early planning phases to pouring concrete and finishing walls, this series will provide the basic knowledge you need to have a successful BuildBlock ICF build.

In video number 18 we explain how to locate ICF attachment points even after they are covered. We also take a look at how to create chases for mechanical, plumbing, and electrical installation.

The videos in this series are produced as a companion to the BuildBlock Installation and Technical Manuals available for free download on the Publications Page or for purchase via the BuildBlock Online Store. You can view more videos in this series via the BuildBlock Blog or by subscribing to the BuildBlock YouTube Page. For a more in depth training experience you can take the free Online ICF Installer Training Series.

Video Transcript

Plumbing, Electrical, and Mechanical Installation

In this video we will discuss how to locate ICF attachment points even after they are covered and we will discuss how to create chases for mechanical, plumbing, and electrical installation.

Finding Attachment Points

BuildBlock webs are outlined on the face of the foam surface of each block. The attachment points of each web are 1.5-inches wide and 15-inches tall. The full face of the web has a pullout strength of 150lbs plus.

Each BuildBlock web also contains 2 patented high-density attachment points which are indicated by the BB on the block. These special hard points have a pullout strength of 450lbs plus and are placed 4 inches from the top or bottom of the block and 8 inches apart vertically. This means that vertically, there is a high density attachment point every 8 inches when the wall is stacked and 6 inches horizontally.

When looking for attachment points, beginning at an inside corner, measure out three-quarters of an inch, this will place you in the center of a web attachment point. From there webs and attachment points are present every 6 inches center to center horizontally.

Creating Chases

Use a hot knife to cut foam and create a chase for electrical wire, plumbing, or other needs after the wall is poured. Tools like hot knives, routers, side grinders, or chainsaws with a guide attached to limit the depth of the cut may be used to easily cut a chase both horizontally and vertically. Using a chainsaw is fast, but creates a greater mess. When cutting chases make them slightly smaller so the wire or conduit fits snugly.

BuildBlock webs are 15” tall and centered vertically in the 16” tall blocks. When two blocks are placed together there is 1-inch of foam between each course of block to allow for chases and plumbing to run horizontally without hitting a web. Vertical runs can easily be made in the foam between webs.


The preferred code compliant method is to install electrical wires or conduit into a snug chase in the EPS foam on the face of the wall. The foam is 2.5-inches deep on each side of the wall.

Cut chases at least 2 to 2 ½ inches deep so the wire or conduit fits snugly and is a minimum of one and one-half inches from the wall face.

This will ensure that screws cannot hit any electrical wires when sheetrock or other wall finishes are attached.

It is recommended when this is not possible a galvanized metal plate should be installed in front of the wire. Consult local codes for specific requirements.

Lastly securely spot glue the wire in place using spray foam adhesive.

Special electrical boxes are available for ICF blocks that mount securely in the foam. Standard boxes may also be mounted and anchored into the concrete wall itself by removing foam and using foam adhesive or tapcon screws to secure boxes completely in place. Boxes with a side flange may be attached to the BuildBlock web

It is recommended that electrical panels be mounted on the ICF wall and be furred out the depth of the panel. Typically this is a small area in a garage or mechanical room. If mounting directly to an ICF wall, a 15-minute thermal barrier must be installed. This can be accomplished by mounting on a 3/4 inch or greater plywood base attached to the ICF wall.

As always, make sure to check local code requirements when planning your project.


Plumbing is integrated into an ICF wall in much the same manner by creating snug chases in the foam and spot gluing using foam adhesive to secure pipes in place. Before cutting, mark the route of the pipe on the ICF wall. Pipes larger than one-inch will impact a web when running horizontally. It is much easier to cut one web versus portions of two webs. Keep in mind that it isn’t possible to install pipes with an outside diameter exceeding 2 ½ inches due to the thickness of the foam. For larger pipe runs, such as those for a water closet vent, ensure those are located on an inside framed cavity wall or fur and frame out a wall to provide the necessary depth.

BuildBlock does not recommend running plumbing inside the concrete wall cavity unless absolutely necessary. Placing a pipe in the wall and pouring concrete around it reduces the structural integrity of the wall and increases the possibility of consolidation issues or voids. Additionally, if pipe is placed inside the concrete and the pipe fails it is inaccessible.

If plumbing must be placed inside the wall cavity, extra vibration is required to ensure proper consolidation around the pipe. For project specific questions or concerns consult codes or engineer’s specifications.

When planning your project, it is always wise to consult with any trade that involves an ICF wall. This helps each trade prepare for their respective installation and eliminate problems or confusion after the wall is poured.

Mechanical Attachment

The exterior surface of the ICF must be covered with an approved wall covering as specified by applicable codes or a current code compliance evaluation report. When a wall covering is mechanically attached to structural members, it must be attached to the flanges of embedded webs or cross ties with fasteners of sufficient length to penetrate through the flange a minimum of 1/4 inch.

Screws placed into the BuildBlock hard point areas take longer screws by a half inch and have additional fastening withdrawal and lateral strength.

The fastener spacing must be designed to support the weight of the wall covering as well as resist the negative wind pressures.

The BuildBlock Code Compliance Research Report (CCRR-1003) details code compliance and additional specifications and information.