Fill Large Voids with Expanding Foam

What happens here

For large and deep voids in the block or stucco wall, expanding insulating foam is ideal. If the hole is very deep, insert crumpled paper or other suitable backing material into the back of the hole first. This provides a surface for the foam to adhere to and prevents it from falling entirely into the block cavity. Then, apply 'Great Stuff' expanding insulating foam, allowing it to expand and fill the void. Let it dry completely.

Goal: Use expanding insulating foam to fill large, deep holes in the wall, ensuring proper backing for the foam to set effectively.