Pinhole (Holiday) Testing – Roof Leak Detection

This test is both non-destructive and highly accurate, being able to detect pinholes in the membrane barely visible to the naked eye. In most cases it has now replaced the need for traditional flood testing, saving considerable amounts of time and water.

We pioneered the use of high voltage leak detection for some flat roof applications in the early 1990’s. Until that time it had been used only for testing bridge deck membranes. It is particularly useful for roof leak detection in single ply and liquid applied waterproofing membranes.Electronic integrity testing of waterproofing membranes, using the Holiday or Pinhole test method, relies on the insulating properties of most membranes and conductive properties of the substrate for the test to be affective.

A high voltage is passed through a copper brush which is swept across the surface of a dry roof. Any breaches are indicated by an alarm triggered when an electrical path to earth is detected. A precise location of the breach can then be located by the operator.

Our Electronic Leak Detection service of waterproofing membranes is widely used or recommended by Roofing Companies, Main Contractors and Material Manufacturers who need the assurance that their waterproofing is free from breaches before completion of a project. For that reason, we have built up numerous, long standing working relationships with contractors in the sector over the past three decades, who have come to rely on our high levels of attention to detail and customer focused ethic.

In some circumstances, however, electronic testing is not possible. For example, EPDM membranes are electrically conductive, in which case Thornton Consulting may be able to offer our Differential Pressure Test, whereby air is drawn through surfactant over laps, thereby testing them for integrity. For further details please contact our office on 01342 410508.

HV Testing for Roof Leak Detection