How do you Build Tight Corners with ICF?

A common question in ICF (Insulated Concrete Form) construction is how to deal with wall dimensions when the blocks lock together in a specific pattern. The answer lies in utilizing a method called the common seam. This technique has become the standard for achieving precise dimensions while maintaining the plumbness of the wall. The common seam allows for adjustments and customized dimensions on-site so that the wall aligns perfectly with the building plans.

The key to a successful common seam lies in reinforcement and preparation. The seam runs all the way through and up the wall, ensuring that the block stays aligned and doesn't shift during the concrete pour. Before pouring, the seam is reinforced with plywood or additional blocks to make it strong enough to withstand the pressure of the concrete. Gaps are filled with liquid foam to prevent thermal transfer, which eliminates cold spots in the wall. This extra reinforcement ensures that the wall remains strong, straight, and energy-efficient, while still allowing for customized dimensions as needed.

The common seam method works around standard block dimensions to achieve the exact measurements outlined in the building plans. It’s a simple yet highly effective solution that has become an industry standard in ICF construction.