Setting the First Few Courses

Welcome to the BuildBlock ICF Installer Training Series: Setting the First Few Courses. This 20 part video series is intended to be an educational walkthrough 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 the 9th video of the series, we cover the basic procedure for setting the first 4 courses of ICF blocks, as well as identify necessary materials and preparation.

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

Setting the First Few Courses

In this section, we will cover the basic procedure for setting the first four courses of ICF blocks, as well as identify necessary materials and preparation.

Before stacking blocks, make sure the footing or slab is clean and ready for stacking. Walk around the foundation and identify locations of doors and window openings. Ensure that the layout is square and that chalk lines are snapped on the foundation.

Stage all necessary materials inside the work area to save time. If you’re only stacking a few courses and then pouring the inside floor of a basement, only stage the materials being used immediately. If you’re staging all materials, be sure to include bracing and alignment systems, forms, foam, rebar, and other materials. Organize materials and tools for easy retrieval and store all material at least six feet back from the future wall. This space allows for easy installation of bracing and alignment systems later.

As you stage materials, understand the reinforcement schedule as well as the specialty blocks and half-height blocks being used throughout the project to make sure you have all the materials you need.

Before stacking verify that vertical rebar from the footings or foundation are sufficient and high enough to comply with non-contact lap reinforcement requirements or site-specific engineering. Drop PVC rings of 1 ¼” to 1 ½” diameter of about ½ to 5/8 in length over all vertical pins.

When stacking block, begin in a corner and work in one direction toward a common seam or window or door openings. Place horizontal rebar securely in the built in plastic webbing as specified once a course is set. For each new course, reverse or flip corner blocks to create an offset running bond. This ensures that blocks lock together as the wall is formed and keeps the webs aligned.

Each BuildBlock form comes with a tape measure and cut lines molded onto the block. When cutting blocks use the cut lines and the 1-inch repeating pattern. Ensure that all cuts are square and clean and place left over cut blocks near window and door locations when possible. Cut blocks can be integrated into ICF walls as long as it has at least 1 web.

After 2 courses have been laid around the structure, shim and trim where necessary to level the block. Leveling the block at this time will ensure the structure stays level for the rest of the build. Use shims to level blocks.

Once the walls are level, spot glue every 18-24 inches. Be cautious of the amount of foam used during this step. Using too much foam adhesive will lift the wall from level and create problems as you continue to stack blocks. Once more block is stacked and the alignment system is attached, a full bead of foam can be placed.

Sometimes the minimum 12” offset requirement of the block cannot be maintained in a wall because of differences between the structures design and standard ICF dimensions. Where blocks come together from opposing corners creating vertical seam, they should ideally have at least a 12 inch offset in in the wall and be 16 inches, or 2 webs, from a corner. If the vertical seam is closer than the recommended 16 inches, use horizontal strapping material on both sides of the ICF wall to secure forms together. Additionally, place bracing on both sides of the wall at the seam.

Strapping can be 1×3 strips of wood, made from 2x or larger lumber of sufficient length and strength. When creating strapping for field cut radii, use a flexible strapping such as Masonite to hold the cut blocks in place. Strapping should always extend at least 2 webs on either side of a seam. When strapping field fabricated corners, especially in larger walls, the strapping must reach back to the rest of the wall at least 2 full webs every course and extend past the corner.

Communication is key on the job site.

Use a permanent marker to mark any special cuts on blocks that will be repeated as the wall is stacked. Agree on a standard system for identifying the size and spacing of cuts.

BuildBlock ICFs all have numbered cut lines every 1 inch. Using this built in tape measure makes it incredibly easy to cut without needing additional tools. Remember that any cut pieces with at least one web can be integrated into the wall in another area. An easy location to use this material is between close door or window openings where strapping is already required.

Lastly, pre-mark any openings on the block itself. Mark the distance to the center line of an opening, size of rough openings, placement of opening penetrations, and the distance from the edge of corners. Marking these before cutting will ensure openings are the correct size and appropriately placed.

For more extensive information review the BuildBlock Installation & Technical manual and other guides available on