The Amount Needed section represents the number of the selected products needed to cover the square footage that was provided by the user. Due to numerous factors that can affect product coverage the output number is only an estimate, not an exact number, & should be treated as such. That estimate is based off approximate coverages when product is applied to New, Unsealed Concrete in perfect conditions & does not take into account other factors like multiple coats. Deco-Crete is not responsible for any issues that may arise from (1) the user(s) misinterpretation of this information as being an exact number &/or (2) technical issue(s) with Calconic© functions.