Conductive Mesh Testing
Built-In Electronic Leak Detection
Some roof systems require a built-in conductive media in the form of a stainless-steel wire mesh called Conductive Mesh. When present, Honza Group is able to perform Electronic Leak Detection by putting a charge directly into the Conductive Mesh with the testing equipment. Think of it as "pre-wired Electronic Leak Detection."
Conductive Mesh Necessary
Conductive Mesh is necessary when a second electrical insulator is introduced. The diagram above shows a roof assembly with a vapor retarder present. When a vapor retarder is included in the assembly, a breach in the membrane alone will not make a connection with the conductive structural deck. Instead, the moisture will get in the assembly and gather between the insulation and the vapor retarder. A breach would have to go through the membrane, all the way down through the vapor retarder, to the structural deck in order for the connection to be made and the breach to be detectable.
In the case where a vapor retarder is used, the Conductive Mesh is installed above the vapor retarder, within the assembly, so an electronic connection can be made, making a breach detectable even if it penetrated the membrane alone.
Note: Conductive Mesh is also necessary if testing is to be done on membranes where the structural deck is not conductive, such as wood. In that case, the Conductive Mesh serves as the necessary conductive substrate.
This diagram shows a roof assembly where Conductive Mesh is not needed. One electrical field is created in the conductive structural deck. The other electrical field is created on the surface of the membrane with the testing equipment. The membrane acts as the singular electrical insulator. If a breach occurs in the membrane, the electrical fields will come in contact with one another and alert the technician of a breach. Since the structural deck is conductive and there is only one electrical insulator, no Conductive Mesh is required to perform Electronic Leak Detection.