Why Does Mold Keep Coming Back in Louisiana Schools?

Chris White • August 31, 2026

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Hey everyone, it’s Chris White with Wynn L. White Consulting Engineers. I get asked about mold in Louisiana buildings constantly, especially the version of the question that really means: we already cleaned this up. Why is it back?


I want to talk specifically about schools because our climate doesn’t do them any favors. Heat, humidity, heavy rain, storms, and long cooling seasons give moisture plenty of opportunities to cause problems.

So let’s start with the question I hear the most.


Why Does Mold Come Back After It Has Been Cleaned Up?

Mold often comes back because the visible growth was removed, but the moisture problem that caused it was never fully corrected.


Cleaning mold and fixing why it happened are two different jobs. A roof leak, plumbing issue, condensation, or HVAC problem can continue supplying moisture after cleanup is complete.


Years ago, I described remediation without correcting the cause as “a dress rehearsal for the next time.” I still think that sums it up pretty well.


We had a client whose relatively new building kept developing mold even after entire areas had been remediated. The instinct at that point might be to clean it again. Instead, we evaluated the building itself, including moisture conditions, air pressure, and mechanical systems, and found several conditions contributing to the problem.


That kind of investigation is a big part of our mold and moisture consulting work, and it’s one reason my father, Wynn White, and I wrote the Mold Prevention Guide.

We Wrote the Book on Mold Prevention in Buildings

What Causes Recurring Moisture Problems in Louisiana Schools?

Recurring moisture can come from roof leaks, plumbing failures, condensation, HVAC problems, storm damage, or humid outdoor air reaching cold building surfaces.


Louisiana schools have a particular challenge. They spend much of the year cooling buildings while the air outside stays hot and humid. That mismatch is part of our climate, not just bad luck.


Common causes of recurring moisture include:

  • Roof and exterior wall leaks
  • Plumbing failures
  • Condensation on ductwork or piping
  • Damaged insulation
  • HVAC or building pressure problems
  • Hurricane or flood damage
  • Extended loss of air conditioning


When humid air reaches cold ductwork, ceiling spaces, or wall assemblies, condensation can develop out of sight.


A stained or moldy ceiling tile tells you where the moisture ended up. It does not necessarily tell you where it started. Treating those as the same question is how a district can end up replacing the same tile three times.


Can An HVAC System Be Part of Mold Reappearing in Schools?

Yes. HVAC systems can contribute to mold when humidity, condensation, airflow, or pressure conditions allow moisture to develop inside the building.


This happens more often than people expect, and the moisture can develop in areas that aren’t immediately visible. If hot, humid air reaches the wrong part of a cooled building, moisture can collect around ductwork, ceilings, walls, or mechanical equipment long before anyone notices a stain.


That is why recurring mold sometimes requires looking beyond the affected material and considering how the building and its mechanical systems are actually working together.


When mold keeps returning, the question isn’t just what needs to be cleaned next. It’s why moisture keeps getting there in the first place.


How Do You Identify the Source of a Mold and Moisture Problem?

Finding the source usually requires combining building history, staff observations, moisture measurements, mechanical information, and targeted testing when appropriate.


I start with the people who know the building best. Does the problem show up after heavy rain? Has the same ceiling tile been replaced more than once? Did it start after an HVAC failure, flood, or extended power outage?


Facility teams often recognize patterns that are easy to miss during a single outside visit.


A mold and moisture assessment can connect that history with moisture readings, building conditions, mechanical systems, and previous repairs.


You can stay very busy cleaning mold and replacing materials, but busy isn’t the same as solved. If the moisture source is still there, you may be managing the problem on a schedule instead of actually fixing it.

Should Schools Test the Air for Mold?

Sometimes air sampling is useful, but it should answer a specific question rather than serve as the entire investigation.


Before testing, ask what you’re actually trying to learn. Determining whether mold is present, evaluating an area after remediation, and figuring out why moisture keeps returning are different questions, and they may require different approaches.


Our indoor air quality consulting may include air or surface sampling, but those results are most useful when considered alongside what is actually happening in the building.


A test result without that context is just a number on a page.


Why Does Building History Matter When It Comes to Mold?

Previous leaks, storms, repairs, and remediation projects can provide some of the best clues about why mold keeps returning.


If the same classroom develops staining after every major rain, that matters. If mold appeared after an extended HVAC shutdown, that matters too. Those patterns can help point the investigation in the right direction.


I sometimes compare it to putting a trash can under a leaking roof. You may have stopped the water from hitting the floor, but you haven’t fixed the roof.


The same principle applies to mold.


Our Mold Prevention Guide grew out of years of seeing these problems and helping building owners recognize the conditions that allow mold and moisture problems to return.


What Did We Learn From Working With Ascension Parish Schools?

Our work with Ascension Parish Schools reinforced that mold and moisture work must produce clear answers school leaders can use, not just identify the problem.


After the 2016 flood, several campuses were damaged, and thousands of students were displaced. Wynn White assisted with mold and moisture consulting, remediation design, site observations, and post-remediation verification while the district worked to keep schools operating.


Our Ascension Parish Schools case study goes into that work in more detail.


Former Superintendent David Alexander described our relationship as:

“What was important to us was important to them.”


I like that quote because identifying mold is only part of the job. The people responsible for the building need to understand what is happening, why it is happening, and what they should consider doing next.


That information needs to be presented in terms they can actually use, not buried in a report that doesn’t help them make a decision.

Wynn and his crew quickly jumped in to help. They showed up with advice, guidance, and true partnership. You can get professional services anywhere. You can’t get this level of dedicated client commitment just anywhere.

David Alexander
David Alexander Former Superintendent of Ascension Parish Schools

What Should a School Do When Mold Keeps Coming Back?

When mold keeps returning, document the pattern, investigate the moisture source, and make repair and remediation decisions based on what you actually find.


Start with a few basic questions:

  1. Where and when does the problem appear?
  2. Does it follow rain, storms, humidity, or HVAC problems?
  3. Could moisture be hidden above ceilings or inside walls?
  4. Have the roof, plumbing, insulation, and mechanical systems been considered, or just the mold?
  5. Would sampling help answer a specific question?


Not every mold problem requires an extensive investigation. In some cases, the moisture source is straightforward, such as a known roof leak or plumbing issue, and the priority is correcting that problem.


But if you’re cleaning the same spot for the second or third time, you already have your answer. This stopped being a cleaning problem a while ago.


When Should a School Bring in an Environmental Consultant?

A school should consider bringing in an environmental consultant when mold keeps returning, the moisture source is unclear, several areas are affected, or the district needs help planning or evaluating remediation.


Before starting, be clear about what you actually need to know. Determining whether mold is present, figuring out why it keeps returning, planning remediation, and verifying completed work are different questions.


I’ve worked at Wynn L. White Consulting Engineers since 1988, and if I’ve learned one thing, it’s that a longer report is not automatically a better report. The information has to help someone make a decision. If it doesn’t, more pages aren’t going to make it more useful.


That is how we approach our environmental consulting work with Louisiana schools.


What Is the First Step When Mold Keeps Coming Back?

When mold keeps coming back, start by figuring out why the area keeps getting wet before you clean it again.


Cleaning the mold and replacing damaged materials may still be necessary. But if the problem keeps returning, cleaning it again without asking why puts you right back into that dress rehearsal for the next cleanup.


After decades of working with mold and moisture problems in Louisiana buildings, I still come back to the same two questions: What caused it, and what needs to change so it doesn’t happen again?


Answer those questions, and you have a much better chance of solving the problem instead of scheduling the next cleanup.


Where Can Schools Get Help With Recurring Mold Problems?

If you’re still trying to figure out whether you’re dealing with a recurring moisture problem, start with the Mold Prevention Guide my father, Wynn White, and I wrote. It walks through these issues in more detail and can help you understand what conditions to look for.


If you already know you have a recurring problem because you’ve cleaned the same area more than once, the moisture source is unclear, or several areas of a school are affected, it may be time to look deeper.


Contact Wynn L. White Consulting Engineers to talk through what you’re seeing and determine the next step.

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In case you missed it, here’s a link to the Indoor Environmental Quality Podcast Episode 8 where I cover Ready.gov and OSHA information on coronavirus. If you’d like more information, email me . Or visit our website www.wynnwhite.com or you can find me on Twitter and Instagram: @chriswhitepe The Indoor Environmental Quality Podcast is available in iTunes (if you’re still running the old school iTunes application!), Apple Podcasts app, Google Play, iHeart Radio, and Spotify.
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