Moisture in Roofing - Thermal and Moisture Scans
When a commercial roof receives annual maintenance or inspections, you're more likely to find trouble before it starts, such as clogged drains, storm damage, and/or compromised seams or flashing. But what happens when a roof leak develops on a roof that hasn't been inspected in years? Where do you start?
A moisture scan using thermal imaging or Electronic Leak Detection (ELD) is the best solution to find wet insulation and areas where leaks are occurring in a large area such as a commercial roof.
Thermal Imaging Using Forward Looking Infrared (FLIR) - A non-destructive test which uses FLIR to show temperatures of various materials in color imaging. Allows you to "see" areas of heat/cold, depending on season and time of day. Areas of heat loss, including wet insulation or gaps in the insulation, will be visible. This helps with area of work determinations for searching for roof membrane breeches and identifying areas of insulation removal and replacement.
Electronic Leak Detection (ELD) - A non-destructive test that uses a brush, broom, roller, platform, or probes, along with low- or high-voltage current, to find breaches, holes, and seam voids in the roof membrane or flashings by completing a circuit with the electrical charge. A breach-free membrane will block any water and therefore, any electrical current. If a leak is present, the water will make its way through the membrane and must touch an electrically grounded conductive substrate directly below the membrane. This allows an electrical circuit to be completed and the testing equipment and technician to accurately pinpoint the membrane breach.
ASTM Guide D7877-14 "Standard Guide for Electronic Methods for Detecting and Locating Leaks in Waterproofing Membranes" lists the four different ELD test methods. Those four test methods are: Low-Voltage Scanning Platform, Low-Voltage Vertical Roller, Low-Voltage Electronic Field Vector Mapping, and High-Voltage Spark or Holiday Testing.
All four of the ELD test methods require the same basic requirements: A conductive substrate must be present directly below the membrane. A valid ground connection must be provided. The membrane must be exposed. The roof system must have a continuous, unbroken electrical path from the top of the membrane to the conductive substrate below.
ELD testing accurately pinpoints leaks in the roof membrane, limiting the repairs needed to the areas where damage has been identified instead of replacing or repairing the entire roof. Although these methods are not a substitute for an annual roof inspection program, they certainly help when making important budget decisions.
While Carlisle does not offer these services, there are many reputable roof inspectors and thermal imagers throughout North America. The International Institute of Building Enclosure Consultants (IIBEC) Member Directory is a good place to start if you want to locate a professional near you: https://iibec.org/membership/search/
Contact Craig Tyler with further questions.
A moisture scan using thermal imaging or Electronic Leak Detection (ELD) is the best solution to find wet insulation and areas where leaks are occurring in a large area such as a commercial roof.
Thermal Imaging Using Forward Looking Infrared (FLIR) - A non-destructive test which uses FLIR to show temperatures of various materials in color imaging. Allows you to "see" areas of heat/cold, depending on season and time of day. Areas of heat loss, including wet insulation or gaps in the insulation, will be visible. This helps with area of work determinations for searching for roof membrane breeches and identifying areas of insulation removal and replacement.
Electronic Leak Detection (ELD) - A non-destructive test that uses a brush, broom, roller, platform, or probes, along with low- or high-voltage current, to find breaches, holes, and seam voids in the roof membrane or flashings by completing a circuit with the electrical charge. A breach-free membrane will block any water and therefore, any electrical current. If a leak is present, the water will make its way through the membrane and must touch an electrically grounded conductive substrate directly below the membrane. This allows an electrical circuit to be completed and the testing equipment and technician to accurately pinpoint the membrane breach.
ASTM Guide D7877-14 "Standard Guide for Electronic Methods for Detecting and Locating Leaks in Waterproofing Membranes" lists the four different ELD test methods. Those four test methods are: Low-Voltage Scanning Platform, Low-Voltage Vertical Roller, Low-Voltage Electronic Field Vector Mapping, and High-Voltage Spark or Holiday Testing.
All four of the ELD test methods require the same basic requirements: A conductive substrate must be present directly below the membrane. A valid ground connection must be provided. The membrane must be exposed. The roof system must have a continuous, unbroken electrical path from the top of the membrane to the conductive substrate below.
ELD testing accurately pinpoints leaks in the roof membrane, limiting the repairs needed to the areas where damage has been identified instead of replacing or repairing the entire roof. Although these methods are not a substitute for an annual roof inspection program, they certainly help when making important budget decisions.
While Carlisle does not offer these services, there are many reputable roof inspectors and thermal imagers throughout North America. The International Institute of Building Enclosure Consultants (IIBEC) Member Directory is a good place to start if you want to locate a professional near you: https://iibec.org/membership/search/
Contact Craig Tyler with further questions.
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