The decision to use efvm must therefore be.
Vector mapping roof.
Electrical field vector mapping efvm is suitable for electrically conductive and electrically grounded roof decks such as steel and reinforced concrete roofs efvm can be used on wooden roofs or precast concrete slab roofs if a conductive layer of metal foil or mesh is applied to the roof deck before the waterproofing layer is installed.
One lead from a pulse generator is connected to this wire loop perimeter.
Over the years we have used many forms of interpretive testing methods such as infrared thermography capacitance testing hygrometers vector mapping sampling etc and found them all to have too many limitations.
As a roofing contractor for 38 years we understand how critical accurate electronic leak detection is for our clients.
Nationwide since 1984 electronic vector mapping is a cutting edge technology that is redefin ing the art of leak detection and quality assurance in low slope roofing and waterproofing systems.
In low voltage vector mapping the surface of the roof membrane is moistened not flooded to create an electrically conductive medium.
The vmg is a specially selected stainless steel grid that serves as a patented conductive medium when used with roofing waterproofing systems that incorporate electric field vector mapping efvm leak detection systems.
By performing the hv test first we find most or all of the puncture type anomalies which may or may not be evident to the naked eye.
A conductive wire loop is laid on the membrane around a section of the area to be tested.
Vector mapping pinpoints breaches in the roof membrane by tracing the flow of an electric current across the mem brane surface.
Efvm is unique in its ability to test the integrity of waterproofing membranes.
Efvm is a low voltage leak test method that creates an electrical potential difference between a non conductive membrane surface and conductive structural deck or substrate which is earthed or grounded.
3 vector mapping felt vmf a non abrasive conductive fabric that can be used under a loosely laid or mechanically fastened roof assembly and embedded into hot liquid membrane systems.
Experience has shown that the best way to provide efficient and budget wise testing is to perform a high voltage sweep on the entire roofing assembly then perform low voltage vector mapping.
Low voltage vector mapping.
The electrical signal from the perimeter cable loop searches for an electrical path over the wet area of the roof to any breach within the wetted area thus completing the circuit to the.