Patent ID: 7602196
Filing Date: 2009-10-13
Classification: E04D,G01M

Abstract:
1. A method of locating a defect in a roof membrane, where the roof comprises a generally horizontal roof deck with a water impermeable membrane applied onto the deck, the method comprising: providing a perimeter conductor around an area to be tested; applying a DC voltage between the roof deck and the perimeter conductor; using a detection probe pair and engaging the probe pair with the roof membrane at different locations on the membrane to detect a voltage generated by current flowing between the roof deck and the perimeter conductor; providing a receiver which acts to detect differences between the voltages detected by the probes; the receiver being arranged to provide to an operator controlling the location of the probes a signal indicative of the differences so as to allow the operator to locate the defect by moving the probes to different locations; wherein the probes are mounted on a rigid common frame such that the probe pair has a fixed separation and the frame includes a handle portion which allows ready manipulation of the frame carrying the probes by the operator.