Electric Field Vector Mapping (EFVM)
EFVM® is a leak detection method based the measurement of the current flow between a non-conductive membrane surface and a conductive substrate ie. a concrete rooftop, balconies, planter box etc which is earthed or grounded.
A thin film of water is applied to the surface to be tested and subjected to low voltage.
The current basically flows towards the leak to exit at the earthed substructure/conductive substrate.
This information allows our measurement technicians to precisely detect all respective leaks, regardless of size, at time of membrane installation or within existing structures.
We are also able to detect breaches/leaks within membranes used on green roofs, car-parks, planter boxes (up to 1 meter of soil) & through tiled/ paved surfaces, which makes it perfect for fault finding those troublesome leaks in buildings.
With this new technology, we eliminate the costly necessity to remove tiles, pavers etc. from the area, as we can test right through them, with pinpoint accuracy.
Let us efficiently detect your leaks and provide you with a comprehensive written report, arming your with the correct information to make the right decisions for your next steps.
HOW DOES EFVM® WORK?
An electric field is created by applying water on the surface of the membrane and using the water as a conductive medium. The EFVM® equipment delivers a low voltage pulsating electrical charge between the non-conductive waterproofing membrane and the conductive structural deck.
A watertight membrane will isolate the potential difference, while breaches in the membrane will cause an electrical connection to occur. Our certified inspectors read the directional flow of the current with a potentiometer to locate the point of entry with pinpoint accuracy.
The EFVM® technicians then complete the test by conducting a visual inspection of all wall junctions, perimeter details, and membrane penetrations. All breaches are numbered to allow for repairs by the waterproofers onsite and are retested to confirm watertightness. A report follows with picture documentation of every breach and a detailed drawing noting the wire placement and breach locations.
ADVANTAGES OF EFVM® TESTING:
Pinpoint accurate, quality-control testing method
Non-destructive integrity and troubleshooting testing
Ability to test sloped decks and vertical walls
Defects can be repaired and retested the same day
Limited use of water required to conduct test
Inclement weather will not hinder the test (wet conditions are preferred for electrical flow)
Overburden installed immediately after the EFVM® test
Eliminates unnecessary removal of overburden to locate a breach when doing a visual inspection
Membrane can be tested prior to the expiration of the warranty or after traffic has occurred on the membrane
Test Area Tile Synthetic Grass Fox FM Roof Top
Test Poor Laid Membrane