There are 2 various ways of computing, a single relies over the familiarity with the world of your walls, and the 2nd volume. It truly is 3 inches thich with slim rebar by it and is supported on joists 18 inches aside. I selected it as it was pretty straightforward https://aac-bricks-plant-cost55213.thezenweb.com/the-best-side-of-aac-bricks-plant-cost-66498501