AN OUNCE OF PREVENTION
. . . OR A POUND OF CURE
Did you know that 60% of the roofs of all newly constructed buildings leak within the first year? Half of those leak from the very start! How does that happen? In a word.... damage. Multiple trades working on both protected and unprotected roofs. And when they leave who's left to clean up their mess? You are!
Oftentimes you cannot prevent the abuse, but you need to find the damage that it produces. So what do you do to ensure that you leave your client with a sound roofing envelope? Flood test? Flood testing takes time and only tests the deck's ability to hold water. It does not test the integrity of the membrane and may even exceed the safe load carrying capacity of the structure or deck. Visual Inspection? You can find the obvious damage and holes but water can still find a way though the smallest of penetrations. . . those unseen with the naked eye.
And attempting to find water penetration points via the old fashioned or traditional way, especially beneath overburden such as greenroofs and parking or plaza decks, is time consuming, labor intensive and costly.
Electronic Leak Detection like the Gaussan HV and Gaussan LV protocols are fast, accurate and affordable. And only Gaussan Tecnhologies uses both tests to provide a much more complete and accurate way of testing. It simply cannot be done any other way and achieve the results that responsible membrane integrity testing requires. It's the "One-Two Punch" so that you can be confident that you're getting what you've paid for. So how does it work?
Gaussan HV (High Voltage Testing)
With a High Voltage sweep of a roof, a testing unit producing a current backed by as much as 36,500 volts of electricity is applied via exploring electrodes to a membrane or coating. If current can pass through penetrations of the membrane and coating, the testing unit will then make an audible sound and often create an electrical arc. Also, the quality of the sound made by the probe or sweep of the high voltage unit is an indication of the soundness of the seam and of the membrane surface itself. Our technicians are trained to listen for and interpret this sound, as well as for the obvious completed circuit alarm along with a minimal voltage drop in the voltage meter.
Gaussan LV Vector Mapping
Low Voltage Vector Mapping pinpoints breaches through a waterproofing membrane by creating a positive and negative electrical plate over and under the non-conductive waterproofing membrane. If there are any penetrations in the waterproofing, current will flow through the membrane and the exact location is detected with Gaussan™ testing equipment. Vector mapping requires water to be on the surface and in the envelope of the roof in order to allow current flow. A boundary wire is installed around the perimeter of the area to be tested and all conductive roof drains or other elements are screened off. To perform the test, the negative side of the Gaussan™ impulse generator is connected to the boundary wire and the positive side to the conductive layer under the waterproofing that is in contact with the building structure.This conductive layer can be the structural roof deck or other conductive elements such as mesh installed in the roofing envelope.
The permanent setup includes boundary cables, access to cable leads if overburden will be installed and mesh if required. Gaussan™ LV is often done in conjunction with Gaussan™ HV, for a much more complete method of testing.
Even new buildings run the risk of roof leaks, especially if they are situated in areas prone to rain and snow storms. Our electronic leak detection can locate any defects precisely and without destroying the existing overburden or disturbing the green roof in any way. And once we have identified the defects, repairs can be made on the spot, assuring a high probability of watertight results.