November 2026

Traditionally, roofing systems have been tested for standards such as fire resistance and wind uplift. Until recently, there was no independent certification standard specifically evaluating Electronic Leak Detection (ELD) technologies with Factory Mutual (FM). That changed in 2022 when FM Approvals introduced Standard 7745 for Liquid Leak Detection.

Factory Mutual (FM) Approval is a rigorous certification process managed by FM approvals, the independent testing and certification division of the commercial property insurer FM Global. These certifications are focused on reducing property damage and helping building owners manage risk. FM testing looks at both individual roofing products and complete roof assemblies.

Unlike many product certifications that evaluate individual components, FM Standard 7745 evaluates Electronic Leak Detection as part of a complete roofing assembly. In simple terms, the standard states testing, certification, design and performance requirements to ensure leaks can be found without adversely affecting the performance of the roof itself.

This FM standard now gives building owners, roofing professionals, specifiers, and insurers a reliable way to evaluate moisture intrusion. Electronic Leak Detection (ELD) is rapidly becoming an important tool for protecting buildings or assets from water damage.

In coordination with membrane manufacturers, FM then tests specific roof assemblies including this ELD technology within controlled laboratory conditions. Roofing assemblies are built to match real world roof systems, controlled moisture intrusion is introduced, and the ELD technology is tested to see how well it detects leaks.

The goal is straightforward: ensure the ELD technology detects water intrusion while the roof continues to meet requirements for fire protection, wind performance, and overall durability.

Detec Systems is the only ELD manufacturer with products certified under FM Approvals Standard 7745. These products include: Detec’s IntegriScan ELD testing equipment, TruGround Conductive Primer and PermaScan continuous moisture monitoring systems.

For architects and consultants, FM Approval assists with specification writing by identifying roof assemblies where ELD technology has already been evaluated and approved for compatibility. Rather than determining whether an ELD product will affect roof performance, designers can reference approved assemblies documented within RoofNav.

Where Can You Find FM Approved Roofing Information?

FM Approvals provides two main tools for finding approved products and roof systems: Approval Guide and RoofNav.

1. Approval Guide

The Approval Guide provides information about individual FM Approved products, including technical details and limitations. To find approved ELD products, search the approval guide for “roof leak detection” and look for one of two categories:

– Manual Scanning Roof Leak Detection Systems. This category is referring to Electronic Leak Detection (ELD) testing equipment used to pinpoint breaches in the membrane. Detec’s IntegriScan is certified under this category. Because conventional roofing requires the addition of a conductive medium for ELD testing, Detec’s TruGround Conductive Primer is also FM approved.  

– Continuously Monitored Roof Leak Detection Systems. This category refers to embedded sensors used for continuous moisture monitoring within the roof assembly.  Detec’s PermaScan-C System is certified under this category.  

2. RoofNav

RoofNav is an online tool that helps users find FM Approved roofing assemblies. It shows which roofing components can be used together to create an approved roof system. Components often include deck type, insulation type, adhesives, and membrane.

The two FM tools work together to ensure compatibility. The Approval Guide confirms whether the ELD product is FM Approved and RoofNav confirms whether that product is approved within a specific roofing assembly.

– In RoofNav, the ONLY approved conductive medium required for ELD testing (TruGround Conductive Primer) is listed as a “Substrate Primer Surface Treatment.”

– In RoofNav, continuously monitored systems are listed as a “Separator Sheet.”

Why Use Both ELD Testing and Continuous Monitoring?

For the best protection, ELD QC testing and continuous monitoring work together. The two technologies serve different purposes. Manual scanning (ELD testing) including TruGround (for conventional assemblies) ensures the membrane is free of breaches, and continuous monitoring starting during construction ensures the roof is constructed without trapped moisture within the assembly. Together, these technologies can:

– Reduce the risk of construction related leaks

– Help support the roof warranty

– Support insurance and loss control requirements

– Extend the useful life of a roof

– Reduce the risk of costly water damage

How Do FM Requirements Affect Each Project Stakeholder?

FM Approval requirements influence decisions throughout the design, construction, and quality control process. Understanding these requirements early can help avoid specification conflicts, material substitutions, and project delays.

– Specifiers – FM requirements influence both the Electronic Leak Detection (ELD) technology that can be specified and the roofing assemblies that may be used. Designers should verify that the selected ELD technology and roof assembly are compatible and listed within the FM Approval Guide and RoofNav.

– Roofing Contractors – Contractors may need to use a different membrane manufacturer or roofing system to comply with FM requirements.  It is also important to verify that the specified ELD technology is FM Approved rather than relying solely on information provided by testing agencies.

– Membrane Manufacturers – In order to have their roofing systems recognized for use with FM Approved ELD technology, membrane manufacturers must participate in FM testing and have their roof assemblies evaluated with the approved leak detection components.

– ELD Testing Agencies – On projects requiring FM compliance, testing agencies must use the FM Approved ELD technology. Confirming compliance before testing begins helps prevent delays and potential conflicts with project requirements.

– Building Owners – Many building owners are unaware of the specific FM requirements associated with Electronic Leak Detection and rely on the design and construction team to ensure compliance. Understanding these requirements early helps reduce risk and ensures the completed roofing system meets the project’s performance objectives.

Here are a few simple steps to consider:

1. Plan Early

ELD components need to be part of the roof design. ELD components should be considered before installation and not added as an afterthought. If insurance requirements are part of the project, involve insurers and loss control professionals early. This can help confirm that the proposed ELD system meets their requirements.

2. Follow Industry Standards

Reference applicable ASTM standards, such as ASTM D7877 and ASTM D8231, in project specifications.

3. Check for FM Approval

Make sure the ELD product is listed in the Approval Guide, then use RoofNav to identify which roof assemblies are compatible including ELD.

4. Consider Including Both Manual Scanning and Continuous Monitoring

Use manual scanning during construction to locate breaches in the membrane prior to starting the warranty and utilize continuous monitoring for ongoing moisture monitoring during construction and for the life of the roof.

A Smarter Way to Protect Your Roof

FM Approvals’ inclusion of Electronic Leak Detection under Standard 7745 is an important development for the roofing industry. It provides a clear way to evaluate ELD technology and understand how it performs within an approved roofing system.

The bottom line is simple: find moisture intrusion early, fix the issues during construction, confirm the building is dry and protect the roof for the long term.

By combining ELD using TruGround Conductive Primer applied directly under the membrane, along with PermaScan-C continuous moisture monitoring during construction, building owners can take a more proactive approach to prevent water damage and protect their investment.