An Opportunity to Correct the Record  

EFVM® testing being used to locate breaches through overburden

Written by Chris Eichhorn, President at International Leak Detection

Every roof will leak…eventually.  Whether on a vertical or flat surface, or underneath overburden or ballast, you can rest assured you will have to deal with a leak at some point in time.  Locating, repairing, and retesting the integrity of waterproofing membranes wherever they happen is paramount in order to minimize structural damage, costs, health concerns, property damage, and potential litigation.

So, when your roof has a leak, what should you do?

Our recommendation is that you research your options, understand what each provider can do, ask for references, and research the facts.

Some of our competitors using scanning platform testing (who came along long after we introduced EFVM to the North American market), like to make some noise about what our EFVM technology can and can’t do.  Unfortunately, their claims aren’t accurate.  It’s important you have the facts in order to select the right leak detection partner.  In this article, we bust the myths and correct the record!

False claim #1 – EFVM equipment is outdated. 

THE FACT IS… EFVM technology was developed in the mid 1970’s, and in late 1990 ILD brought it over from Germany and adapted it for the North American market.  We periodically tweak the equipment to enhance performance for bare membrane and troubleshooting testing.  Just as the automobile of today was founded on technology invented in 1886 but continues to evolve and improve over time, so it is with EFVM technology.  The EFVM testing method is in compliance with the ASTM standard for electronic leak detection (ASTM D7877- Standard Guide for Electronic Methods for Detecting and Locating Leaks in Waterproof Membranes).

EFVM® testing locates breaches on vertical surfaces

False claim # – EFVM technology can’t test vertical surfaces and walls. 

THE FACT IS… EFVM testing is absolutely suitable for vertical wall testing!  Depending on the height of the wall, the technician can detect breaches from either the perimeter conductor wire or can create a “picture frame” of the conductor wire to perform the test.  Unlike the testing methods of others, ILD does not need to bring additional equipment to the site to perform an integrity test on vertical surfaces.

EFVM® testing can be done in all weather conditions

False claim #3 – EFVM cannot test through overburden. 

THE FACT IS… ILD delivers a distinct advantage when it comes to green roof testing: there’s no need to tear up the sod.  Our EFVM test works through most layers of overburden, including insulation, soil, planters or trays.  We’re proud to have worked on some of the largest green roofs and plaza systems in North America.  Our inspectors can pinpoint the location of each leak, finding that proverbial needle in a haystack.  When it comes to preserving the integrity of your sustainable roof, ILD provides a sustainable solution. To verify EFVM testing feasibilities, contact our technical sales department for guidance.

False claim #4 – VMG (Vector Mapping Grid) does not have any wind uplift ratings with either CSA (Canada) or RoofNav (USA). 

THE FACT IS… There are several approved wind uplift ratings with VMG in a roof system. Check the RoofNav website ( for wind uplift ratings.  The material name is “grounding screen” in the roof composition ratings.

False claim #5: EFVM technology is not as effective as scanning platform testing. 

THE FACT IS… Some leak detection methods are able to identify an area of a suspected breach, but are not able to pinpoint the area of the leak without manual intervention.  With EFVM testing, we can pinpoint a membrane breach with exact accuracy using the reading probes only.  We’re not guessing where the leak is, we know where it is.  At the end of our inspection, we provide you with a detailed report showing all breaches and their likely sources.  The report includes digital photo documentation of the breaches, roof CAD drawings that pinpoint the measured location of breaches, and a detailed drawing noting the wire placement. We also clearly mark each breach on the membrane surface.  Clients have found our reports assist in segregating liability and are critical for membrane warranty.

ILD® technician conducting EFVM® testing

EFVM Technology Advantages:

  1. Pinpoints the exact location of a membrane breach 
  2. Defects can be repaired and retested the same day 
  3. Non-destructive to the membrane 
  4. Requires only a limited use of water 
  5. Effective on vertical surfaces 6. Can be performed in inclement weather 
  6. Can be performed on sloped structural decks 
  7. Eliminates removal of overburden to locate a breach and overburden installation can proceed immediately after or during testing 
  8. Expert technicians test your roof – there’s no need for you to buy our equipment and hope your team is proficient in locating the leak 
  9. We have a 20-year track record – others can’t come close to the 500 million square feet of membrane we’ve tested!

While we’re flattered by the attention of our competitors, the fact is that EFVM is efficient, effective and non-destructive and has become the modern standard for integrity testing.  ILD introduced North America to electronic leak detection and we continue to be the global leader offering the most accurate integrity testing system on the market.

The Right Partner Makes a World of Difference!


About the Company

International Leak Detection (ILD®) is a world leader offering advanced technology in leak detection and smart roof monitoring.  Since 2001, our proven expertise and proprietary solutions have provided building owners with peace of mind performance and protection.  Every flat roof will leak eventually, are you ready?  Discover the ILD difference:, 1.866.282.5325,



Tel. 866.282.LEAK (5325)