Electronic Leak Detection for Roofing Systems

A building’s roofing system separates the damaging outdoor environment from the valuable interior contents. To be effective, it must be watertight. Although roof systems are inspected and sometimes flood tested prior to warranty issuance, small, difficult-to-see breaches in the membrane system can go unnoticed until damaging water leaks occur inside the building. Moreover, once a leak has developed it can be extremely difficult to locate the leak and perform the necessary repair, especially when overburden materials are installed.
Enter Electronic Leak Detection, otherwise known as ELD. ELD systems have been around for 20+ years and are gaining popularity due to some revolutionary new products that have expanded testing capabilities. ELD systems come in two main varieties: low-voltage and high-voltage, with low-voltage being the most common. ELD systems work by creating an electrical potential difference between a non-conductive roof membrane and a grounded conductive structural deck or substrate. Testing is performed by applying water, which is conductive, to the surface of the roof membrane. The roof membrane will isolate the potential electrical difference between the deck and the water, but when a breach is present, the water will create an electrical connection to the grounded deck, pinpointing the exact leak location to the testing technician. A major benefit of ELD testing is that it can be performed at any time, even after overburden materials are installed.

For ELD systems to be effective, a conductive substrate must be present directly below the membrane’s surface. Due to this requirement, membrane choice and application method can be limited.
Two ELD companies that Carlisle has experience with are International Leak Detection (ILD) and Detec Systems. Products from either of these companies are permitted for use in a Carlisle warranted roof system but are not covered in the Carlisle warranty.

ILD has been around since 2001 and promotes a conductive mesh that must be installed directly below the membrane for accurate testing of membrane systems over non-conductive decks. Due to the design of the conductive mesh, it is only acceptable for use under thermoplastic FleeceBACK^® membranes adhered with FAST™ or Flexible FAST Adhesive.

Detec Systems promotes a conductive primer called TruGround^® that is roller-applied over the top layer of insulation, prior to adhesive application. Once dried, the membrane system can be installed as usual. TruGround conductive primer expands ELD testing capabilities, as it is suitable for use with bareback membranes and even black EPDM, which historically has not been compatible with ELD testing. Carlisle SynTec Systems has secured FM approvals for Detec’s TruGround in a number of different roofing assemblies. Those assemblies include:

EPDM and TPO with CAV-GRIP^® III adhesive over SecurShield^®, SecurShield HD, DensDeck^® Prime, and SECUROCK^®.
PVC with Low-VOC Bonding Adhesive over InsulBase®, SecurShield, SecurShield HD, and SecurShield HD Plus.

 Contact Chris Kann with questions regarding ELD systems.