Inside an ICF Monopour Foundation on Grand Manan

Part 1 of the High Performance Builds series features Mark Wille, Aron Jones, Shaun St-Amour, and Audree Grubesic. It was published Feb. 28 and runs 3 minutes.

Project overview

Offsite Dirt Network filmed the project on Grand Manan in Climate Zone 6A. The episode follows the early stages of an ICF monopour foundation. The crew focuses on layout accuracy, thermal performance, and airtight construction.

Foundation layout

• Traditional batter boards were used for layout.
• Painted reference lines marked center of wall, outside of wall, and outside of footing.
• HD monopour brackets were used.
• The brackets are fully reusable.
• Grade pins were hammer-drilled into the ground because the site sits on a solid wedge rather than loose soil.
• The layout used bearing points and compass orientation instead of a surveyor.
• Property line setbacks still had to be maintained.

Fastfoot and reinforcement

• The project used Fastfoot corners.
• Rebar stabilized the Fastfoot system.
• Rebar chairs created challenges during the first phase and were moved out of the way.
• Rebar sizing followed Part 9 of the National Building Code and the ICF Manufacturers Association manual.
• An average 12-inch rebar mat was required.

ICF wall assembly

• The ICF system is a flat-pack design.
• Each panel has 2 5/8 inches of EPS foam on the interior.
• Each panel has 2 5/8 inches of EPS foam on the exterior.
• The concrete cavity is 6 inches.
• The nominal R-value of the foam alone is about 23.6.
• The full assembly is intended to improve thermal performance and airtightness.

Airtightness and performance

The concrete is placed within insulated layers, creating a continuous air barrier. After the concrete cured, informal testing confirmed strong resistance to air movement. The episode treats airtightness as a key part of energy efficiency.

Schedule and crew

• A three-person crew completed the foundation layout on day one.
• The work ran from sunrise to sunset.
• Aaron Jones and the Big Dog Construction team chose a smaller foundation as their first monopour project.
• The smaller scale was meant to reduce risk and help the team learn the process.

FAQ points from the post

• An ICF monopour foundation combines insulated concrete forms with a single continuous concrete pour for footing and wall.
• Monopour foundations reduce thermal bridging and improve airtightness.
• Climate Zone 6A requires assemblies that manage moisture, limit air leakage, and maintain insulation.