How Can Nuclear Moisture Scanning Equipment Help Find Roof Leaks?

If you’ve dealt with a roof leak that just won’t quit—despite repair after repair—you’re not alone. It’s incredibly frustrating to spend thousands of dollars and still feel like you’re chasing ghosts every time it rains. At Weather Shield Roofing Systems, we’ve been helping commercial property managers and facility owners get real answers for over 40 years. One of the ways we do that is with advanced diagnostic tools like nuclear moisture scanning equipment to find hidden roof leaks no one else can detect.

So, how does this technology work—and why does it matter for your building?

What is nuclear moisture scanning?

Nuclear moisture scanning is a non-destructive testing method used to locate moisture trapped beneath a roofing membrane. It works by sending low-level radiation into the roof system, where hydrogen atoms (which are found in water) absorb and scatter the radiation. The scanner then detects these changes and indicates where moisture is present.

In plain terms? It can see where the water is hiding under your roof, even if there are no obvious signs on the surface.

Why did this church still have a leak after so many repairs?

Recently, we received a call from a church with a chronic roof leak on a ballasted EPDM commercial roofing system. The leak was small, only showing up a few times a year—but it had been going on for a long time. They had already spent thousands of dollars on patch jobs, but the problem kept coming back.

That’s when they called Weather Shield Roofing Systems for help.

Instead of guessing, we brought out our nuclear moisture scanning equipment to do a full diagnostic sweep of the roof. Within 20 minutes, the scanner identified a 24-inch by 24-inch patch of wet insulation—an area no one had thought to check before.

When we inspected that precise spot, we found the culprit: a tiny pin hole in the membrane. It was so small, it had escaped notice in previous inspections. But thanks to our scanning technology, we were able to find and fix the issue in less than an hour.

How accurate is a nuclear moisture scan?

Very. Nuclear scans are one of the most reliable ways to detect moisture beneath the surface of a roof, especially for systems like:

• Ballasted EPDM

• Built-up roofing (BUR)

• Modified bitumen

• Older single-ply systems

They are especially useful on large roofs where leaks are hard to pinpoint and for roofs with chronic or intermittent leaks—the kind that come and go depending on weather, temperature, or building use.

While visual inspections and infrared scans can help, nuclear scanning goes deeper and tells you exactly where moisture is present in the insulation, giving you a clear repair plan instead of a guessing game.

What are the benefits of using nuclear moisture scanning for roof leak detection?

Here’s why building owners, property managers, and facility teams trust this technology:

1. Pinpoint Accuracy

It identifies exactly where the moisture is, even in hard-to-see or hidden areas. No more tearing up large sections of the roof looking for a leak.

2. Faster Repairs

When you know where to look, your roofing partner can make repairs quickly and cost-effectively. Like our church example—it took under an hour.

3. Prevents Further Damage

Undetected moisture doesn’t just cause leaks. It can degrade your insulation, compromise your roof’s structural integrity, and lead to mold growth inside the building.

4. Cost Savings

By eliminating guesswork and unnecessary repairs, nuclear scanning helps protect your roof investment and lowers your long-term roof maintenance costs.

Is this the right solution for my roof?

If you have a commercial roof with ongoing leak issues, especially if it’s:

• Older

• Ballasted

• Complex

• Multi-layered

…then yes, nuclear moisture scanning could be the most accurate and cost-effective solution to diagnose and fix the problem. It’s also a smart option if you’re preparing for a roof replacement or warranty claim, and need documentation of existing moisture levels.

How does Weather Shield Roofing Systems use this technology?

At Weather Shield, we don’t believe in band-aid fixes. Our approach is always to diagnose first, then repair. That’s why we invest in tools like nuclear moisture scanners—so we can give you straight answers and transparent recommendations.

Once we’ve found the problem, we provide cost-effective repair options that extend the lifespan of your commercial roof and reduce long-term liability.

Can this technology work for small leaks?

Yes—and that’s what makes it so valuable. Many of the worst leaks start small, and they don’t show up in obvious ways. Water can travel along insulation, deck seams, or even through walls before it reveals itself inside the building.

That’s why traditional patching often fails. You’re only treating the symptom, not the source.

With nuclear moisture scanning, we identify the exact moisture path and correct it at the root cause, not just the visible leak.

How much does a nuclear scan cost?

This is one of the most common questions we hear. The cost depends on several factors:

• Size of the roof

• Roof system type

• Location and accessibility

• Whether the scan is part of a broader roof inspection or maintenance program

That said, it’s almost always cheaper than repeated leak repairs, which often stack up into the thousands over time. Plus, by identifying hidden wet insulation, it can prevent structural damage and save you from having to replace the entire roof prematurely.

At Weather Shield, we’ll talk you through the pros, cons, and options before starting any service—and we always offer cost-efficient solutions that make sense for your roof and your budget.

If you’re tired of wasting time and money chasing roof leaks that keep coming back, our nuclear moisture scanning services can provide the answers—and the relief—you’ve been looking for. We’re here to help you protect your building, your budget, and your peace of mind.

Reach out to us today and let’s talk about how we can help!

Ben Cornell

Account Executive

Ben Cornell is a lifelong West Michigan resident who began his career in commercial roofing in 2006—originally just looking for a summer job to help pay for college. What started as temporary work quickly turned into a lasting career as he steadily advanced through roles in estimating, project management, service leadership, and sales. Today, he serves as an Account Executive at Weather Shield Roofing Systems, where he continues to thrive in a company that has supported his professional growth every step of the way. Ben’s long-standing commitment to the commercial roofing industry is fueled by his passion for helping clients and the strong team culture at Weather Shield.