Definitions

Breakthrough Effect describes the phenomenon where the radar pulse is reflected off the first interface (surface of the medium) and detected by the receiver. This can mask any defects at shallow depth. This depth depends on the frequency used, the higher the frequency the lower the breakthrough effect

Leaf delamination is a common occurrence in masonry walls. It describes the process whereby an air void is created between two leaves. This can happen if the in-fill of the wall is of a material that can be consolidated. Water can infiltrate the wall and wash away this softer material. It can also occur if a leaf begins to deform, or crumbles and separates from an opposing leaf.