Which statement about foundation drainage membranes is NOT true?

The statement that foundation drainage membranes should not be installed on older foundation walls is not true. In fact, these membranes can be effectively installed on older foundations as well as newer ones. The purpose of a drainage membrane is to manage water flow around the foundation, helping to prevent moisture accumulation and potential damage. Installing them on older structures can be beneficial if those foundations are experiencing moisture issues, as the membranes can improve drainage and reduce the risk of hydrostatic pressure against the foundation walls.

Options pertaining to installation below grade, providing an air space between the earth and the foundation, and being typically sealed at the top are accurate. These features highlight the functional design of drainage membranes, which help ensure that water is directed away from the foundation, thus improving the long-term integrity and safety of the structure.