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Top Real Estate Agent Training - Mold Testing & Cleanup

Updated: Apr 26, 2022


There is a ton of misinformation about mold, how to test for it, how to clean up, how to do things correctly. It's because in certain states like in Arizona, there's no rules, there's no laws, you could start a mold cleanup business tomorrow with no experience, no training, no certifications.


Why should you listen to me about mold testing is because I've done thousands of mold remediation jobs, being called in as an expert to do testimonies, I do rebuttal type things for when you have some other company that did testing and it's maybe not quite right. I'm going to give you the right answers on how to do this stuff. I am a licensed mold assessor in the State of Florida. The very first thing you should know is that, if you're going to do testing in the beginning to see what kind of situation you have, and then you're going to clean up mold, and then you're going to do testing afterwards. That would be the right way, the three-steps involved. It should not be the same company. You can imagine the bias that would come in if I say owned a company that clean up mold, but I also came in and said, "Oh, hey, we'll do the testing and see how bad the mold is." Then we'll tell you how much it should be cleaned up. Then by the way, we'll check our own work afterwards just so that you know that you're in good hands. It's totally unethical in the environmental world, that's not how things work. You have a separate unbiased third party who will do the front-end testing and the back-end testing, no matter what kind of testing it is, the people that clean it up are a separate entity so that you don't have any of those biases.

Financial Bias

Another misconception with mold and mold cleanup is who's in charge of what gets cleaned up and what doesn't. In places like Florida, Texas, Tennessee, where there's licensing for this. Again, the assessor, the person who comes in and does the initial assessment is the person who writes out what needs to get cleaned up and I'll explain why. If you're a homeowner, you're like, "Wow, yeah, fixed at all." If you're an insurance company and you're like, "No, don't fix anything. We don't want to write a big check." If you're the remediated who does the cleaning up, you have a financial bias to have the largest cleanup possible. If I charge $500 to come in and do a round of testing analysis and all the things I'm going to show you today, I don't care if my recommendations as a $1,500 cleanup or $15,000 cleanup because I got paid my $500 to tell you what the story is. One other analogy I like to tell here, because people get all weirded out. You see mold under their kitchen sink and then they just lose their minds. You can take a step back from it and not be so emotionally charged when you see that. If you imagine go into the doctor's office, they draw your blood work, your cholesterol comes back a little high. Initial evaluation, initial testing. The doctor says, "Hey, you should probably exercise a little more, eat a little healthier, and take this pill." Well then what happens three months later? The doctor wants another round of testing just to hopefully show that the cholesterol levels and come back down. In the mold world, it's the same thing. Initial assessment, cleanup, post assessment to show that it's all been cleaned up correctly. Here in Arizona, nobody recommends the post cleanup. What ends up happening is either people go in and rip stuff up, let's say it's a flip they tear out a bathroom that's all bulleted out. They don't take any of the proper precautions that I will show you today. Then you and your client walk into this beautiful home and they did a pretty good job with a flip. What you don't know is that there's all this airborne and mold flying around from everything that they ripped up in that bathroom. That's why we would do some sampling. Let's see what I have next here.

Mold Evaluation

Before I get to that, one other thing that sometimes people ask they go, "Well, let's just say a window has a sprinkler spraying on it for a long time in time and the water has come through the wall and there's mold on the wall." Well, somebody might go, "Well, why in the world are you going to charge me an extra $300, 400 or 500 to do a mold evaluation? I can see that there's mold, of course water, we know that there's a problem and I need to clean it up. Yes, but the analogy I like to give is, if you're going to spill a bag of flour in your kitchen and you're not going to clean it up for 3, 4 or 5 months, where is that flower going to end up? If I were to wait for an answer, you would say things like the floor, all flat services, ceiling fans, your air ducts. You have to think of mold just the same way. Once it dries out and becomes airborne, it starts spreading throughout the house. Again, if I'm going to come to do the evaluation, of course, we know that there's mold on the wall, that's common sense. But the question is, how expansive is the problem, I have a three-story house that I'm talking to you right now, is it just by that window in the kitchen area or is on the first floor and on the third floor, and it's spread all around for several months because we didn't notice it. That's why that initial evaluation is important because it's hard for me to tell you how to clean it up properly if we don't take the sample that tell us how big the problem has become or how small it's become.

Again, a $400 evaluation might save you thousands of dollars from that mediator coming in and telling you that you need to clean all three floors, the air ducts and all these other things that really isn't necessary. Again, but they're trying to create work themselves.

Home Inspectors & Mold Testing

One of my biggest problems with mold and mold cleanup is that home inspectors basically go out and get a pump and sample kit, which I'm going to show you later, and then they start doing samples. Then they charged the same thing that we charge and they give you like, I'm just going to say, they give you a shitty report. They basically give you a copy of the lab results. They give you a terrible two-page version of what they did, which is like, "I took a sample of 15 liters per minute above," but they don't actually give you any of the cleanup. They don't give you, "Hey, we found problems. This is a problem and why?" Because they don't know, they don't have any idea. They just learned how to use the pump and the air sample and then they forward you the lab results and like, "Good luck, men, it's your problem. I don't know what to do with it." Don't hire people like that. They charge the same thing that we do, but the difference with us is we actually give you the full remediation protocol if we do find problems. We know how to interpret the lab results and to tell you whether there is a problem or there's not a problem or there's potentially a problem that it can't be found right now. How do I put this like, you would be hiring an electrician to come look at your electrical panel who can't actually do the electrical work or, "Well, if you don't tell me how to fix it, why should I listen to you about what the problem is?" Another thing to think is, if you went to the doctor and got your blood work done but then afterwards, all they did was give you the results, no parameters, no highs, no lows, and no conversation with the doctor afterwards. They're like, "Good, your your oxygen is 6." "Well, is that good? Is that bad? Does that mean I'm in trouble, medically?" You're like, "I don't know. I just do the blood work." You really want to work with people that actually know how to clean the problems up and how to give advice to all the parties involved.

Mold Standard of Practice, SOP

Problem number 1, I see all the time. If you go to this website, you can just Google it,, there is actually a long checklist of everything that we're supposed to check when we do a mold evaluation. Again, 90 percent of the home inspectors have never even heard of this website. What they do is they come in, they do a little look around, they take the samples and they send you the results. I actually did a home inspection and the guy who was buying the house owned a mold remediation company. He brought his team in to do a pre-evaluation test and it was missing all kinds of things. They had no idea what they were doing and this is the guy that owns remediation company. I kept my mouth shut but I find that super annoying. If you were to go to this website, you would see that it's pages and pages and pages. Basically what it is, is it's a water version of a home inspection. In other words, you're still supposed to look at for roof leaks, for rain gutter issues, for drainage issues. You look at all the plumbing, you look at all the HVAC. It tells you when you should consider this sample versus that sample, should you take a five-minute sand or 10-minute sample. It really does lay it all out loud. Again, most inspectors have never seen it so when they give you their mold evaluation report, what it actually says instead of saying all of that, it says, "Well, here's the sample and how long it took it for what I was running the pump at, a plump was calibrated on such and such date." You're like, "None of that matters." None of that needs to be put into a report. None of that's important. What's important is that the things that basically lead to mold, water problems are those things that are happening now or things that you can prevent in the future. If you go to that website and your client or, whatever, a buyer on one of your listings is, using an inspector that doesn't know about this, you got to tell them they're wasting their money. The first part of this website I was showing you was that evaluation which is a visual, you should be taken to this, should be photos, should be videos. It should have the same defects that you expect to see in a home inspection, leaking roof gutters, loose toilets, missing cog, what else? Let me think here, broken faucets, basically anything that can lead to a water problem down the road. As you probably know, I don't want to get too basic here, we have a really dry climate.

Where is Mold?

So sometimes in places like New Mexico, Arizona, Colorado, people they go, "We just don't have that big of a mold problem." But the reality is, mold is everywhere. If I were to take a sample right here, right now, there would be mold in the sample. The question becomes, do we have indoor sources of mold? Neighbor's dog is gone crazy, you can hear that. The first thing we need to do is do that visual mold of aggregation. Let's see here. Second thing is we need to do technical measurements. This is going to be temperature, humidity, and carbon dioxide. Obviously, if we had like six college students living in a dorm and they will all shower in the same area with no exhaust fan, that's going to create really high levels of humidity. Sometimes one of those air conditioners you put maybe a mother-in-law suite on the wall, if they're failing that blow out like 98 percent humidity. For mold to grow, we know that we need water and we need a carbon source. So dry wall, wood, etc. Sidebar here, if you're in a really old home like a 100 year old home and it's basement and the basement is made of plaster. Plaster is not carbon-based, so just to see water staining, discoloration and you're like, "I wonder if that's mold." It's not going to be mold because there is no carbon sources inside that plaster whereas if you're in an older home and let's say there's a little water leaker and humidity issue, and what's that stuff called? The glue on the wallpaper is like pure carbon and you can pull a little bit away and mold love growing on there. That's why we look at the technical measurements because if the humidity levels are out of whack, that will be the source of water. You might not have a water leak, but if you have high humidity. Once you get to 60, 65 percent humidity, that is the source of water for mold to grow. Giving an example of what I saw, in Florida, I owned a inspection business and we do a lot of mold work. We would be called in, there would be snowbirds and they would come back from the summer and basically the air conditioner had broke for a month or two. You're ending up with 85, 90 percent humidity in a condo high-rise and basically you'd have a little thin layer of mold on all the furniture, all of everything so we'd have to do the whole evaluation, write it up, and then it was thousand dollars to clean it. That's the big difference between here and somewhere like Florida. Let's just say I had a water leak in my ceiling and there was a little bit of mold, and I didn't quite clean it up properly, well, here if the air conditioner breaks, we're not usually going to get 60, 65 percent humidity it's Arizona. If this same house were in Florida and the air conditioner breaks, then the humidity comes back in the summer time and then the mold will start to grow from the humidity. That's the big difference. Once we've done the visual evaluation, technical measurements, we are then going to do what's called moisture mapping. We take a thermal camera and basically scan every part of the house. You're looking for window leaks, ceiling leaks, plumbing leaks, roof leaks, any source of water that can be there right now. I've seen one where like the [inaudible] line going through the wall, was overly condensating and there was all this excess water in the wall from that. Thermal cameras picked it up, we couldn't see any of it visually.

Written Mold Report

Again I learned how to do this from environmental engineers and from industrial hygienists. I'm going to take their word on how to do these things properly over, say a home inspector with a problem. When you write up your conclusions in the report, it would say previous sources of water, yes or no, active sources of water, yes or no. Elevated airborne levels, which we'll get to in a second and then was there visible mold. Those are the four areas previous water, current water, visible mold, airborne mold. Then we're going to get to the sampling, this is where it gets to be a little bit fun here.

Let's talk about the general rules of sampling where people make mistakes. You would almost never take samples in crawl space, in an attic, in a garage, in the wall, 99 percent of the time you take your samples in the living space. Because really what we're doing it's we're trying to determine air quality, and the breathing air quality inside of our houses. You don't live in your attic, you don't live in your garage and you don't live in your crawl space. Technically, those are considered exterior area rooms because if you think of crawl space, lot of times they're vented, the air just goes through, the attic is purposely vented. None of that attic air a crawl space air unless you have ducting problems, is actually getting into the house. That's not to say that if there's mold under the house and mold in the attic it doesn't get cleaned up. It does, but it's not as significant [inaudible] because it's not an indoor air quality breathing air problem. This is what we do. I've got a pump right here. Looks like this. This is a wireless one. I'm sorry the battery operated one. Excuse me. You can see it here. What we'll do is we set this on a tripod, if someone's not putting on a tripod, again, that's a mistake. Basically we put on a tripod because we don't have to have it really close to the breathing level. We set it typically for five minutes and then we put this little my sample on it.

Mold Air Sample

Where is my sample? Sample looks like this. We take the little tape off, sorry, I've already used this one but I'm going to pop it open again so you can see it. Save a piece of tape so we can cover it up, you're with me here? We've got two sides, we have a flat side and we have around side. The round side goes down and we hit our sampler and we take it for five minutes. Now what we're going to do is we're going to do, one outdoor sample, and then we're going to do at least one or two indoor samples. If it's a really big house, you might do more. You can actually do some research and if you want to go super deep on this stuff, if this is like a thing that's for sure going to end up in court, you might end up with three outdoor samples, one into the wind and one away from the wind, and a the third one. But again, it gets cost-prohibitive for your typical homeowner because you're talking about a $1,000 or 2,000 for the sampling there. Whereas we want to keep this like $3, 4, 500. Once this is done running, we go ahead and we pull it off and then we seal those back up. Seal it both sides and basically, we'll put that in a plastic bag where the chain of custody that says when we sampled where we sampled, who was sampled for. Then we take those samples down in the lab. What the lab actually does, what most people never see, I have already cut it.

Inside here is a microscope slide, a lot of people don't know this. This side is sticky. That side, if we had to let this run, there would be a thin line of debris on there and it's the same debris that you see when the sunlight shines through your windows. We can actually measure all things, fiberglass, insect parts, human skin cells, plant parts I'm trying to think what else. There's a whole long list of things that we can actually test for it. But in this case, we'll do it for mold. There's a whole bunch of different kinds of mold. Basically they put a little region on there, put it under the microscope and look at it, 600 times magnification and they're going to count how many little mold particles around here. That's the reason we kept track of how of the air, 15 liters per minute I was telling you. Because we want to tell them that we took five minutes, 75 liters, they do the math on how many cubic meters of air that is and they say, this many counts per cubic meter of air. Then what we're really doing is, the level of matter a little bit, but what really matters is that the levels are significantly different or then significantly above what is outdoor levels. That is an airborne sample. That is again, 99 percent of the samples you're going to take. You could also take, if you have visual mold somewhere, you can take, that's a swab sample right there, or this right here is a tape sample. There's basically one square centimeter there. You would just go up against the material that you're trying to test, push that up against there. Then again, they can look at it under the microscope and see what's going on in that one square centimeter. Because it's exactly one square centimeter, again, we could do the math to tell us this is how many counts per blah blah blah. Then when we get back from them, if you can see this, this is a recent one. In the wintertime, you don't have very high mold levels, but we have our outdoor sample. We have a first floor sample, and we we second floor sample. The first thing we look at is total counts. Here we had seven or 20 versus indoors we had 90, and then we want to look at is here we had nine Aspergillus, 40 Aspergillus and then here we had one raw counts. Literally one spec of mold on that second floor sample which equates to 40 per cubic meter. Again, this is why you cannot just interpret these lab results in a vacuum. You have to have the visual inspection, you have to have the moisture mapping and you have to have the technical measurements. This is 25 percent of it, so we put all of that together because I've seen really crazy things happen. I've seen aquariums that are well taken care of me, be the source of indoor mold. It doesn't have a water leak, you can have like a house that's really dirty and you've got mold and mildew in the shower areas. Again, this does not by itself constitute a problem just because you have some mold inside the house and there wasn't in the outer sample. You might have plants in the house that are the source of the mold. I'll tell a story later, you might have like moldy cheese or moldy bread. An indoor source of mold can really be lots of different things. It doesn't have to be, oh my gosh, I have a water leak. Let's see here. They are stage samples, swab samples, [inaudible] going to talk about that.

Mold Results

Sometimes, I get something like this bag. Here is the problem, it's not perfect because we had just a little bit of mold, which isn't zero. But also, it is not significantly high like these numbers. When you have a real mold problem during the the tens of thousands in the summertime, these outdoor samples can be 6,000, 8,000. Again, your clients will be like, ''Oh my God, it's 80.'' Again, they don't have any parameters to go after that. But at the summertime, 80 is nothing because the mold is everywhere. That being said, here's what we do when we have something that's like a slight elevation, but the rest of the inspection wasn't cause for considering the old water leaks, the current water leaks, though, active like mold. This still could mean that there's some weird problem behind the walls inside air ducts that we couldn't visually see that day, so we have a write-up. Again, most people just ignore it, if it's coming out, that's fine. But the write-up basically says, ''hey, you can do a quick wipe down with the HEPA [inaudible] flat surfaces and then let the HEPA filters run for two-days or maybe three-days, and then re-sample, and that gets you to zero. That's the totally by-the-book answer. Again, most people don't do it because usually, this means nothing, but we have to write that up. Because when you do enough jobs, every once in a while, six-months from now, somebody might go to replace their air handler, and they pull it up, and there's all of this mold down underneath the air handler because there was a condensate in an area that was inaccessible in the house. In that case, these very low levels did actually indicated a problem, it would have took destructive measures and the base of measures for us to have ever found that problem. That's why we have to have that right up. Your final report should look like this. It should be a full whatever, 30,40 pages because there's lists of all of these defects in the house that have a water-related plumbing, and exterior, a