Healthy Living Spaces® by Daniel Stih

You paid for mold remediation, the work is done, and a musty, mold-like odor lingers. Learn why a lingering mold odor means something is still wrong - and how to find and fix the source of mold contamination in your home.

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The Remediation Is “Done.” The Mold Isn’t. 
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TRANSCRIPT

Today's episode is on why your home still smells moldy or musty after you've had mold remediation done. You paid for remediation, the work's done, and a mold or a musty odor lingers.

Here's what it means and how to get rid of the odor. You're not imagining it. You walk through the front door, you breathe deeply, and then you notice the faint smell.

The mold's supposed to be gone. Your house still smells musty. So some homeowners assume a lingering odor is normal.

It's not. There's a musty odor. Something's wrong.

You don't have to live with it. I'm going to break down what it means and what to do. First of all, mold odors are from what they call microbial VOCs.

We all know the word VOC from a can of paint, volatile organic compound. Mold makes similar compounds are volatile, meaning a room temperature. They get in the air, they off gas, and these come from flatulence.

Basically, mold doesn't have a stomach. It secretes enzymes. Out in the open, it breaks down the wood or the drywall, the materials in your house, the carpet, into something you can eat.

And the smell, just like you, depending on if you're going to eat broccoli or brussels sprouts, something healthy, you have some flatulence. Depends on what you eat, same thing with mold.

The smell is going to vary, depends on the type of mold and what it's eating. So how do we get rid of it and why is it still there after mold remediation? Also, by the way, in terms of health problems, it's prudent avoidance.

It is a VOC. It's a neurotoxin then, technically speaking, meaning it's affecting your brain, how you think maybe, even if you don't smell it.

Why there might still be a musty odor? Number one, it could be the source of moisture wasn't identified and fixed 100%.

When you're having remediation done and you tear open a wall or a ceiling, that's an opportunity to really investigate and confirm, oh yes, that is the source of moisture, because sometimes we know we find the mold when things are dry.

And you don't rebuild until you really verify, oh I fixed a leak, now let me see what happens when it rains out. Oh yeah, water doesn't come in, and then I'll rebuild.

A dehumidifier some people try to use to get rid of this odor problem helps a little bit, but this is only because whenever there's more moisture in the air, things smell more, everything.

If you've got perfume or scented soap in your house, when it's more humid, you're going to smell things more. That's everything that smells, that's how these volatile organic compounds work. More moisture in the air, things smell more.

So sometimes people think, oh, the mold came back because it's raining, it's humid, I smell the mold now. The mold's not coming back. You're smelling the odor because the mold never went away.

It's just you smell more now that it's humid. And when it dries out, you might smell less. That doesn't mean it's okay.

Let's go find the problem. Number two, here's the problem. Most of the time, the remediation company didn't remove all the mold.

They're still hidden mold. It's because remediators focus on what they can see and what they estimated. It's hard, I might even argue impossible, to estimate the extent of hidden mold.

You can estimate it - you can't know it. It's impossible to know the extent of hidden mold.

Often these estimates -  the workers just follow them verbatim, and they stop at the exact boundary of what was specified in the estimate when they should have kept going, except they're not mold inspectors.

They're just workers and they're not supervised. And the supervisor is just trying to close a job and get a paycheck from you. So they're not being careful enough.

And then what happens is air pressure changes in your house can pull odors from room to room, just like when you open a window and you get a draft going. You turn on a dryer, turn on the cooking, the range cooking stove hood, a bathroom fan.

Those are going to suck air, and that's going to make a draft pull air from these wall cavities and spaces where they're still mold hiding and cause you to smell stuff more or less. Cross contamination is not one of the reasons for mold odor problem.

What I mean is often remediators set up the negative air pressure wrong. They don't do it properly even though they're charging you, and dust gets spread throughout your house, mold spores. That's not what's causing the mold problem.

It is improper that you paid for it and they couldn't set it up right. Sometimes, however, contents, something porous, an old piece of furniture, an old rug or even a new rug.

Maybe it got wet, maybe it's just rubber backing on it that smells like mold and is not mold.

That you didn't notice before because there was, the old analogy is, you couldn't notice this sound of the dripping faucet for all the hammering going on during the construction project. Now that the hammering stopped, you notice the drippy faucet.

Maybe you're noticing something now that's not related to the mold project. Use your nose, sniff it down. Sometimes during these investigations, I tell clients, just empty the whole room.

Let's just get it done. If there's something in here that's causing the smell, let's just make it simple. Move it all into a different room or garage temporarily so we can see, oh, it's none of the stuff.

Sometimes it is. Hopefully you do this before remediation begins. If you're starting with a quote mold odor, you should try the odor investigation first before you do a mold test.

Find some mold. Think mold's causing the odor when it's not. Number four is HVAC system wasn't addressed.

This is another one you should do before you start with remediation. HVAC system is your heating ventilation, your heating air conditioning system. It's an odor distributor.

Every time it runs, it's circulating air throughout the house everywhere. So what if that's the actual problem? Save the money.

Don't get distracted by the quote mold remediation. Often, it's the coils, the drip pan where the condensation happens inside the air conditioning and you just can't clean it.

If there's some HVAC contractors who are out there jumping up and down going, I can clean it, Daniel. Yes, but you're going to be using some toxic chemicals. Those have new odors.

Now for some people, maybe that'll work. The odor will go away. They can deal with the chemicals.

And to save $10,000 on a new system, let's try that. And what's the risk? Because if we budget to replace it anyhow, and it smells and it doesn't work, no money lost.

But you have to be aware that there's risk involved. They're basically canisters that they spray, like air canisters, except they have chemicals in it to clean the goop off your coils in your HVAC system, try to dissolve it, make it all melt away.

They can't get into all the nooks and crannies. So you just got to replace the system. Do this kind of investigating before you jump on the mold project thinking, that's my problem.

Masking the odor. Some people think they get rid of the smell by using ozone machines, or there's air fresheners or the chemical deodorizers. And these, of course, just mask the odor.

Ozone is one to really be careful of. It goes out and reacts. It oxidizes, just like a fire oxidizes with oxygen when it's burning wood.

It reacts with everything, not just mold, and it can cause new odors that then you're stuck with. You don't know what it reacted with. The rubber backing in your carpet, your leather furniture, and you have a new problem.

Don't do the ozone. Find the source of the mold and get rid of it.

How do we eliminate the musty odor? You paid the remediation company. There's still a mold odor.

By this point, I'm getting down to the fact that it is, the odor is in the area there was mold. You paid the remediation company to get rid of the mold. The odor is still there. What does it mean? There's still mold. They missed it.

You need to help them find it. It's actually not the remediation company's job to find it. They're not the inspector.

They're not that kind of investigator scientist. That's theoretically what your mold inspector is for. So, I'm going to walk you through the process.

I have a document I share with clients and remediation companies that I developed after being in the middle of this kind of argument on whose fault is it. I got rid of all the mold. It's not my fault.

There's still mold. What do you want me to do now? I got rid of all the mold.

And the client's going, I still smell mold. Do you miss something? How do we figure out whose fault it is and who pays for it?

I'm going to read you some of the excerpts and simplify it down here. Documents called Supplementary Information, Mold Remediation, The Contractor's Responsibilities, and Post-Remediation Verification Testing.

You see it abbreviated a lot, PRV. PRV means Post-Remediation. That means after the mold remedier's done, the verification testing is basically the mold test afterwards.

Here we go. 

Contractor bids. What I'm doing is I'm setting clear who's responsible for what.

The Contractor will conduct abatement activities in areas noted in the inspection report provided by the consultant, your mold inspector. What's in the mold inspection report.

It is possible that after remediation begins, further mold is identified, and then the scope of work is going to have to be expanded to include the newly discovered mold. Meaning it was an estimate I gave you. It goes farther than I thought.

You need to pay me more. The contractor will not be responsible for the removal of materials outside areas identified in the report without a work change order, authorization by the client, et cetera, et cetera, to the initial bid. It's fair, right?

Post remediation verification testing.

The contractor, most contractors aren't aware of this, but in the standard for mold remediation, the S520 standard for professional mold remediation, which every mold remediator, I'm sure, will tell you they have a copy, it actually says in there the contractor is responsible for what is called a post remediation evaluation, and that they do that prior to calling the mold inspector to retest. And it further says that this isn't supposed to include a visual inspection to ensure the surfaces are clean, as well as an olfactory one. It can't smell, it's not supposed to smell. You're not supposed to call the mold inspector to retest if it still smells, and of course, that you make sure that you do moisture readings and surfaces are dry.

Post remediation verification, now this is where you call the consultant, the mold inspector. First, perform a visual inspection. It's got to look clean, plus this is where the tape lifts are important.

Let's say there's a stain or something and you can't tell if it's mold or not mold. You do a tape lift. I, myself, I bring a microscope.

I'm trained to identify mold.  I bring the microscope with me. So let's do it right there.

Yes or no, mold or not mold. That's the easy one, right? When you're doing an inspection, there shouldn't be any rot.

Why? Because if it's rot, that means it got so wet, it's so bad, could be stinky, it's not clean. Nothing should be rotted.

Nothing should be dirty. I once did a commercial project where the builder, commercial builder, paid the remediation company because they made a mistake. Things got wet, the builder's trying to do the right thing.

Builder calls me to do the post-testing. He's there shadowing me, watching me what I do. Things are pretty dirty.

There's dust everywhere. Now mind you, it's a fine white dust. It's subtle.

It's so subtle that I'm being careful not to tell the contractor the bad news. I'm trying to think of how can I break it to him gently that this is not okay. I'm not going to air test why.

It's not clean. Well, this guy's pretty smart, right? He's been in business long enough to know when he's being conned and something's just not common sense.

So he's doing the white glove test. He's not wearing white gloves. He's just using his finger, rubbing his finger over the door jams, the window sills, the floor and going, It's dirty, Daniel.

I know. That's not okay. We're not going to start testing the air and go, we got good air test.

We're not going to go, does it smell like mold or not? It's dirty. Move on.

Call the contractor back. Moving on is last one, must eat or mold like odors. So if any of these are true, I just walk away, call the mold remuneration company, come back.

I don't do air sampling because you know, you can get good air samples even though things smell bad and they're still mold. But let's say we did air samples and the air samples look bad. Or say it smells bad, but the air samples look good or both.

A scenario where something's not right and we all agree it's not right. What do we do now? This is the real meat of this document and why I prepared it.

I'm going to frame it with interpreting the results of the air samples, for which the air samples don't look good. They don't pass the criteria, because that's probably a more common one, easy one to grasp your head around.

But same thing applies if it still smells musty, same procedure.

So they don't pass the criteria. Several possible reasons why there's still mold in the air or still an odor. Number one, they contain an area in the surfaces and it were not adequately cleaned.

The contractor should be familiar with the Healthy Living Spaces document. I have another document on this. Suggestions for cleaning and passing clearance testing and how to really clean.

As well as the S520 that talks about how to really clean. That's what you're getting paid for. That's the hard work, not spraying the chemicals.

This is number one possible reason. Number two, and I'm going to get to later what we do about it. But number two, these are the reasons.

Number two reason for things are not okay. There's still mold in the work area, and this mold is close by to where the mold was identified in the original inspection report. Here's some examples.

The contractor removes part of the wall and stops short of removing all the mold in the wall because he goes to the line of the estimate.

Just go, you know, 10 feet and stop in the estimate, and he stops at 10 feet and he should have gone 11 or 12 or 15. If that happens, the contractor should just return and remove the additional drywall.

Another big one, and this is why in my document, my reports, it's always, you remove one side of the wall, you remove the other, because the common one is, they removed one side of the wall where there's mold, but not both. What do they should do?

Come back and remove the other side of the wall. And that should have been an estimate to begin with, and if you're the mold inspector and didn't put it in there, maybe it's your fault for us having to go round and round.

You should just hold them, take both sides out to begin with. Now, sometimes, remediators don't want to take both sides out because maybe there's cabinets on their side, or a bathroom, a kitchen, something that's going to be real difficult.

Then it's the homeowner's job, homeowner's responsibility to the mold inspector and remediator need to tell you about this, that you make the decision. No, I'm willing to take the risk. Let's just do one side.

Often, however, they don't educate the client about that, the homeowner. They do their work. They only estimate to take it off on one side, and then it fails, and then they're going to go back to a work change order.

The problem with that is, they've drug you through the mud now, in time and money, doing things twice, and they should have brought you in in the first place and asked you, hey, what's your opinion?

And remediators, you're making this too hard on yourselves. I understand it's a tough business. It's easier if you let the client make the decision.

Educate them and go, look, we can take off both sides of the wall if you want to get it done right the first time. I mean, we can go two feet past where we think there might be a mold if you want to get done the right the first time.

Or we can give you the cheaper estimate. Just made the job more complex than it needs to be. Remember, moving on.

Another one is there is mold in the work area, but not close to where the mold was identified in the original inspection report. Now whose fault is this? You know, the mold inspector's got a tough job too.

Often it's because the client might not have asked them to test all the areas. Or, very legitimately, and this is why we even do the post verification at all in the first place, it's not just to make money for the mold inspector to do air sampling.

It's because you can have mold someplace hidden with no idea, no stain, no water damage, no paint peeling, no idea it's there. That's why we're doing all this testing. And then, you're like, well, where is it?

How do I know?

And a lot of some mold inspectors will just, since they can't tell you where it is, they'll just try to go, oh, you know, it's not that bad, or it's close to acceptable limits, or it's below a known health standard to cause health effects.

They're missing the opportunity in the whole point. Because they can't tell you where the mold is, they're going to try to underplay it sometimes, possibly overplay it or find some other excuse instead of simply acknowledging, I don't know.

How could I possibly know? So what do we do to find it? I'm going to get to that.

For now, again, it's just possible reasons for us failing. Admit this one. It's not in the area you did the estimate for in the inspection.

We don't know where it is. Here's an example. Room with two skylights, a big great room with two skylights.

The initial investigation report only found mold to be present in one. The skylight looked water damaged. But they didn't test both skylights because the other one didn't look water damaged.

And the air test or the musty odor is still present in the work area, but technically the mold is not in the place it was estimated to be.

The only way to determine what is actually true is either have the consultant test the other area or have the contractor just remove, in this case, the drywall plaster from the other skylight part, to visually investigate and find is there mold there

or not. Another reason is there's mold in the building outside the work area. Now this one is similar to the skylight example, except now the mold is in a complete different area of the house or the building.

In the air, either with the musty odor or the mold spores in the air samples in the work area, they're being contaminated with mold from a different part of the building. Now the solutions.

The only way to tell which of these is true is to do something. You can't think about it anymore. You have to do one of two things.

The first one would be, which is quite common, the contractor simply re-cleans the area, soap and water, or often it's the spray, the chemicals, which actually don't work. Simply re-clean the area and they call to have the air re-tested.

In this case, if the air tests are satisfactory, the air re-samples, the samples are good, the mold odor goes away, which by the way is a reason not, don't use soap or chemicals to have fragrance, because if you do, it's going to smell wonderful like

the odor went away when all they do is spray some fragrant chemicals. I demand that nothing but plain soap and water with non-fragrant soap, non-fragrant dish soap, such as that from seventh generation or someplace else, free and clear be used,

otherwise I can't do my job. And if I can't do my job, I tell people I can't do my job, the remediation company, I tell them, I can't do the inspection. It says to do an olfactory inspection, evaluation.

I can't do it, because you use these chemicals. Not my fault. If the contractor just re-cleaned, and you get good results, and it's not because you use a perfumey soap, it's the contractor's fault for failing the first mold test.

And I would argue they should have to pay for that second mold test. Number two, how you tell which is true. What do you do?

You get the consultant, that would be me or the mold inspector, and the remediator, and we go in there, and we basically pause, take a deep breath, and attempt to think, where could there be more mold? And then we gotta do something.

Either I test another area, or I go just cut the other skylight open. And then if additional molds discovered, they give you bid, remove the second skylight. And now if the retest are good, you conclude cleaning was not the issue.

Rather, there was still mold. And if it was in close proximity to the original estimate, it might be the contractor's fault.

Moreover, it's discovered outside the area, it's not the contractor's fault, and a new work order needs to be required to remove the additional mold.

An example would be the contractor's, it would be the contractor's fault if materials simply weren't removed two feet in all directions past the original mold or water damage noted in the original inspection report.

But if the molds discovered some far distance away, the contractor is not responsible. Now, here's the key thing, and this is why I wrote this document. You can't know which of the above is responsible for bad air test or bad odors.

You can't know until you either re-clean an area and re-test using non-fragrant soap, or remove some other random area that you just go, well, I wonder if the mold's here. And then the smell goes away and re-test.

Only after you re-take the air samples or re-evaluate the odor, can you determine which one was true. So in the meantime, the contractor is panicking because he's like, I need to get paid. I did my job.

And the homeowner is like, no, you didn't. There's still mold. And the contractor is like, well, I don't want to do any more work.

I estimated this. I did a great job. I know I did.

And the homeowner is like, well, no, you didn't. It still smells.

The only way to know is it the contractor's fault, or is it not the mold inspector's fault, but we're only human, is after you take action, either re-clean, re-test, or go cut some more walls open and re-test.

Now, for a real world example, way back in the late 90s, when I was getting in this line of work, I retired as a, well, I say retired just after 11 years left my engineering job. I have a degree in aerospace and engineering.

I worked at Motorola Semiconductor for 11 years. I moved to a small town, became a handyman, and I got sick. And so I started testing for what was making me sick.

That's when I got into the mold testing and into air quality studies and business. As I was transitioning, my first mold remediation job, now I understand you're not supposed to do both mold remediation and testing. This is for my grandmother.

She's sick. She's not feeling well in her house. She wants me to do a deep cleaning of her house, during which I find mold.

I carefully uncovered some wood paneling and found some mold in the drywall behind the wood paneling in her home. I put it back, didn't touch it. I said, now if you buy me an air scrubber and a HEPA vacuum, etc., etc., I will do the remediation.

She didn't trust anybody else. Turns out that the source of the moisture was in the kitchen.

This is the kitchen under the kitchen sink, and you could tell the clues were the snipped old pipes versus the new pipes, plastic pipes versus new copper pipes. Everything was dry.

She bought this house with this mold in it, dry and moldy without knowing it. So I'm taking out her kitchen cabinets. I'm taking out her stove and refrigerator because the water whipped up the walls behind the appliances.

I'm cutting out all the walls. There's no cabinets or walls left in her kitchen. I think I'm done.

I should be going to test the air. I can't. I won't.

Why? It still smells. In fact, I think it smells more now that I took up the vinyl flooring and opened the walls than before.

It's not right. It's common sense. So what I did was I drilled a small hole in the floor and I put my nose up to it.

Oh my gosh. What is in the floor cavity? And it turned out, of course, all this water, if it's wicking up the walls, it's going in the floor.

All the insulation was yucky and it's dry, but it's from the sawdust on it and stuff. During construction, little bits of dirt moldy and smells yucky. In the woods, there's rotted wood, there's moldy wood.

It is a mess. And that's when, fortunately, happened early in my career, I realized how significant the smell is in doing your post-testing. If I had tested the air with the floor closed up, I'm sure I would have gotten good air samples.

Now, how does the smell get out and not the mold spores?

Well, there probably are a few mold spores getting out, but by the time it's diluted with all the other air in the house and inside and outside, I'm not going to be able to save looking at a spore trap mold test result that, oh, you still have mold

in your house and it's in the floor. I could if I did, if I stuck a tube into the floor and sucked the air out of the floor, that's called a wall check, even though we do it in floors and ceilings and whatnot.

I originally called the wall check, stick a tube someplace, sucked the air from that location. But at this point, I saw the mold, I removed it all, so I thought, and I didn't really need to do that because I could use my nose.

Guess you have to have a good nose. If you don't trust the client, trust someone who says there is, I get it all the time, people go, I smell mold. Wonderful.

Tell me where exactly. Point me in the right direction. End of the story, clean that up, smelled good.

Nana, who they were accusing of losing her memory, having Alzheimer's, not being as sharp as she used to, she returned to being sharp as a tack.

I will also add that even though I couldn't pinpoint what it was, prior to this remediation and cleanup, whenever I go over house, I'm like, something's just not right. It's not like I feel bad, it's just something's kind of just doesn't seem right.

And afterwards, smelled clean, felt wonderful. That's the rest of the story. If your home still smells moldier must be after a mold remediation project.

Something was missed. Either you still have a moisture problem you didn't fix right, or you still have hidden mold. The smell is not going to go away on its own.

Don't settle for it's good enough. There shouldn't be a mold odor after mold remediation is done. At Healthy Living Spaces, I specialize in helping homeowners identify what others overlook.

I use the science, the testing methods, and just practical common sense and solutions I've learned over the years to help people. If your home still smells moldier must be after a mold job, I can help you figure out what others have missed.

You're a mold inspector, you're a mold remediation company, we can do a three-way call. We can figure it out, schedule consultation on the website Healthy Living Spaces. Go there to schedule consultation.

Thanks for listening. Until next time, I'm Daniel Stih.