What is Attic Mold and How is it Harmful?

Hey folks, Pete Ferrante here. Welcome to my informational series where I look to help you navigate the waters of environmental abatement and hazardous material removal.

I’ll be taking a sort of layman’s, easy to approach fashion to these questions to provide as much value to you as I can.

In our new series, we’re diving deep into attic mold to answer any potential questions you may have.

Pete Ferrante is the President and CEO of FERRO Environmental. He specializes in full spectrum abatement and remediation — such as asbestos and soil remediation — and is committed to bringing the top industry talent to his clients’ projects. The result? FERRO regularly appears as a PROFIT 100 Company in Canada.

He also sits on the Board of Environmental Abatement Council of Ontario (EACO) and the Toronto Construction Association’s Environmental Committee.

What is Attic Mold?

So, Pete. We know what regular mold is. But what makes mold, attic mold?

You know the thing is, attic mold is just mold.

Whether it’s in your basement or your attic behind the drywall, the reality is it is simply mold. There are certainly different strains of mold, but it’s not like there is only one that likes to proliferate in the attic. It doesn’t happen that way.

Mold really only needs three things to proliferate.

The 3 Things Mold Needs to Proliferate

1. The Introduction of Mold Spores

It needs, obviously, the introduction of the mold spores.

2. Mold Needs Food to Grow

The food being drywall, wood, or any kind of cellulose-based product. These are the most prevalent when it comes to mold that you would typically find in the home.

3. And Don’t Forget Water

And then, of course, it needs a source of water.

Typically what happens in attics and why you get attic mold more commonly is that a lot of times there’s really not a lot of air circulation up there. You’ve got elevated temperatures — elevated humidity — in an enclosed space that doesn’t have a lot of circulation.

I mean it is kind of like the perfect storm for mold. That really is why you get most of it up there.

Is Attic Mold Harmful to People?

Is it harmful to people? Mold can be, let’s put it that way.

I don’t think you should panic and I don’t think you should run screaming from your home when you identify some mold in it. But the reality is mold typically acts much like an allergen.

Those are the symptoms you’ll typically run into. Kind of like cold or flu symptoms, allergy symptoms, or sometimes difficulty breathing. Maybe some headaches at the odd time, irritation.

But the reality is, like any allergy, for some, it does not affect them at all, and for others, there could be the slightest amount in any given area and they react badly.

Attic Mold Acts like an Allergen

The worst of it happens really when you’ve got people that have a compromised immune system. Elderly people and young children who don’t have a fully developed respiratory system yet, that sort of thing, they’re probably the most at risk.

So yes, it can be harmful, but yes it can also be dealt with. If it’s done properly there’s no reason to panic.

Weirdest Example of Attic Mold

You’ve seen a lot of mold throughout your career. What is a memorable instance that stands out?

Yeah, you know, the crazy thing is the weirdest example isn’t even, you know like I said mold can grow on anything. But man, the weirdest example?

You know we’ve walked in and there are some cultures that really enjoy high humidity. So we’ve walked into some units and man oh man you know they’ve got humidifiers cranked, more than one, cranked to the max.

You’d think it was a rain forest in this place.

And the mold was so thick on the walls it looked like carpet. It was ridiculous.

And somehow — and again it ties back into how susceptible people are –I don’t know if these people had even one allergic reaction. And then meanwhile a couple of the people that we walked in with immediately got stuffed up, had a hard time breathing, the whole thing.

It was crazy, it literally looked like a carpet on the walls.

How To Identify Attic Mold?

Now that we know what attic mold is and what it needs to grow, what exactly can you do to identify it?

Well, the easiest answer there is you know you have a mold proliferation if you see mold. I mean that’s the easiest way to identify it.

Sometimes you’re not going to see that, it’s not going to be quite that obvious so look for the symptoms.

Obviously, mold growth is the easiest way to identify it. You can look for water intrusions and usually somewhere around there you’ll see some mold growth eventually if it’s not dealt with quickly and properly. You’ll be able to see staining.

Learn More about Mold Removal:

Identify the Proliferation of Mold Behind a Drywall

If you’ve got a proliferation of mold in behind drywall you’re not necessarily going to see that mold on the outside. You may see some water staining or some enzyme staining.

That will tell you there’s something going on behind the wall.

You can certainly look for it that way. If you’re standing in any given room and you’ve got water staining on the ceiling, obviously, that tells you that you’ve got water penetration coming through that has been pounding on the top of that ceiling.

You won’t be able to see the mold yet, but if it’s been there long enough and it’s been wet enough, I’m sure that if you were to cut out a portion of that drywall and run some intrusive testing, you’d probably find some mold.

Those are the most common symptoms or most common ways to identify it.

How to Prevent Attic Mold

Once the mold is removed — either by myself or with a contractor — what steps can I take to ensure that more mold doesn’t develop in the future?

The beauty of other dangerous materials, like asbestos, is that once you remove it, it’s removed. It’s not going to grow back or re-proliferate itself in the same area. It just doesn’t work that way.

Mold, on the other hand, is exactly the opposite. If you don’t solve the problem, it can and will come back.

That is provided on if those three factors exist: a source of food, water, and the necessary mold spores. That’s the reality of it.

So what can you do to prevent it?

Well, the first thing you can do is don’t give it that cocktail of things that help it grow.

If there’s a leak coming into the building, into the home — into the attic, the basement, whatever it is — make sure you stop that leak. And when you first remove any mold, make sure you get it all, as much as you can possibly find.



The Limitations of Antimicrobial Sealants and Encapsulants Around Attic Mold

There are antimicrobial sealants and encapsulants that you can use. But, the reality is that they’re effective for only so long.

I’ve seen mold growing on these things after a given period of time if the conditions are right. And if the conditions are right and they’re right for long enough, mold will grow on almost anything.

You might say, well you know mold won’t grow on surfaces like glass.

You’re right, but you know if that glass is neglected long enough and there’s water intrusion, guess what? We’ve all seen mold growing on window sills, on caulking that’s in the windows. Heck, even if there is enough dirt and dust on the glass, the mold will grow on that.

If it’s specifically in an attic, for instance, turn around and make sure you get better ventilation.

Put a couple of more roof vents up there, put a turbine style vent up there, you know, get the air moving around better. That will reduce the humidity which reduces the ability for the mold to grow.

If you’ve got roof leaks, if you’ve got shingles missing, just get that stuff replaced. If you’ve got bad caulking, replace that.

The more that you can do to prevent any intrusion of water, the less likely that you’ll see that mold grow back.

How to Decide if You Need Help Removing Attic Mold

What is the threshold for someone saying, “Hey, I can do this myself,” or “Hey, I may need help,” when it comes to attic mold?

You know it boils down to a couple of things. Comfort level is a big one, and listen, some people are just handier than others. If you have a background in construction and renovation and that sort of thing you’re likely a lot more comfortable and able to certainly remove Level 1 mold, or even approach Level 2.

But the thresholds are much the same as the asbestos industry.

Explaining the Levels of Attic Mold

  • Level 1 (0 to 10 square feet) – This requires fewer precautions, but someone would still need personal protective equipment and respirators, that sort of thing.
  • Level 2 (10 to 100 square feet) – Now you need an enclosure. You need to handle, contain, and dispose of the mold properly, and you need to disinfect the entire area.
  • Level 3 (100+ square feet) – This is another stage up. You need full containment, full personal protective equipment like a Tyvek Suit, and respirators with P-100 filters.


For Level 3 situations, you may even have to go with a powered respirator, which actually makes it more difficult to work. Your productivity is going to go down when you’ve got a full-face respirator, and really even when you have just a regular half-face respirator.

For example, you’re not breathing as easy, you’re sweating more, and ultimately, you’re working harder to perform the same amount of work.

Level 1, most people can handle without really much of an issue. For Level 2, I would still recommend getting an environmental contractor to take a look. And for Level 3, I would highly recommend getting an environmental contractor to come in.

Listen, the reality is at the end of the day, the challenge is the liability. Once they’re aware of it, everybody has it, nobody wants it. And the way you mitigate that risk is by having professionals do the job.

How To Remove Attic Mold?

OK, we’ve identified the attic mold, how can you remove it?

There are a bunch of factors there and it depends on how handy you are.

Unlike asbestos removal, there are no regulations that say mold must be removed in this way and that you must have this level of qualification in order to do it. Anybody can claim to be a mold removal expert, as they don’t legally require any sort of certification in order to do that project.

Which kind of makes me nervous as a hazmat contractor. But I digress.

The reality is yes, you can, you are capable, there’s nothing stopping you legally from doing it on your own. Smaller amounts of mold, absolutely. You don’t need a professional contractor to come in to clean your bathtub tiles or minor things like that.

Mold remediation is broken up into three categories: Level 1, Level 2, and Level 3. And while there are no regulations, there are industry protocols to be aware of.

The two most popular in Ontario are the EACO protocols (Environmental Abatement Council of Ontario) and the CCA protocols (Canadian Construction Association). Both have a step-by-step walk-through.

You can actually go on to our website at ferrocanada.com where we have downloadable copies of both.

  • EACO Protocols
  • CCA Protocols

What Levels of Attic Mold Can You Remove Yourself?

For smaller amounts of mold (Level 1), I absolutely see no reason why you could not fix it yourself.

But anything bigger (Level 2 and Level 3), I highly recommend a contractor. Depending on your level of knowledge, Level 2 is doable by yourself.

However, you need the experience to know where to look, where to keep going, and how to decontaminate the whole area properly so it doesn’t potentially spread. So, if Level 2 is out of your ballpark, contact a specialist.

Why You Should Hire a Contractor to Remove Attic Mold

We’ve discussed what attic mold is and when to decide if you need a contractor, but what are the actual benefits of hiring a contractor compared to just doing it yourself?



Well, the reality is environmental contractors like myself exist for a reason.

When you want to get it done right the first time, when you want to make sure that the health and safety of your family, your employees, your tenants, whatever it happens to be, is first and foremost, you need to get it done properly.

You don’t have the luxury of doing it over and over again, hoping that your air test passes.

The reality is you want to hire a professional contractor when you’re looking to get it done properly. If you’re a landlord or a building owner you have an obligation to your tenants and the people that occupy that building to provide a safe and healthy workspace so you should bring in professionals to get it done, it’s that simple.

Do I Have Any Financing Options for Removing Attic Mold?

I’m sold on hiring a contractor, but what options do I have to finance it?

I don’t know of any other contractors that actually will assist their clients in procuring funding to perform — usually larger scale — remediation projects.

We work with our financial institution and they’ve jumped in and helped finance projects for our clients. I know that condominiums and condominium corporations have their own ability to arrange financing, but we also can go through the main financial institutions.

There are secondary lenders, smaller banks and credit unions, that sort of thing, that are happy to finance construction projects. And it really all depends on the situation the building is in and the credit rating.

But again, we’re happy to work with our clients and find the turnkey solution to make sure they can get their projects done properly.

Choosing the Right Environmental Contractor

I’ve heard a lot of horror stories about contractors who maybe don’t get the job done correctly. Do you have any tips on hiring the right environmental contractor?

Actually, that brings up a great point. There’s several firms out there — several hazmat contractors — that are trying to be all things to all people.

Don’t buy that. Don’t buy that nonsense.  

I mean you know today they’re hanging wallpaper and tomorrow they’re mold abatement contractors. And you know what, we’ll also do the testing for you and write the scope of work. And hey, you know what, we’ll do the air clearance testing at the end of the project.

Just don’t buy that nonsense. There’s a reason why schools don’t let kids grade their own test papers, right? There’s a reason why people don’t get to prepare their own tests and then test themselves and then give themselves a grade. There’s too much opportunity for nonsense.
You know, having said that, FERRO will provide a turnkey solution. But we make a point of bringing the right people to the project for you. It’s just that simple.

We bring in third-party consultants that deal directly with the end user.

They go in independently, do the assessment, do the testing, get their lab results and prepare the scope of work based on that. From there, once they do the scope of work, it gets handed off to an environmental contractor like FERRO.

We perform that scope of work. The consultant would come back in, assess the situation, say yes the scope of work as it was written is performed. They’ll do an air test.

Again, a third party.

They’ll do the air test, analyze the results of that air test, and then give you a pass or a fail. And if it’s a fail they’ll ask you to re-clean. FERRO doesn’t fail very often so we often come back and say, “hey everything looks great.”

It’s passed, the air clearance testing has passed. You can take down your enclosure, bob’s your uncle, everything’s back to normal.

I just really have a problem when contractors — it’s usually contractors — try and do the whole thing in-house. There’s too much opportunity for nonsense, impropriety.

Just avoid it, just avoid it, make sure you’ve got independent people doing what they do best and you’ll always come out on top.

FERRO Environmental Can Help You with Attic Mold Removal

By all means, feel free to reach out if there’s anything that I haven’t addressed, or if you have a specific project or question that you need answering.

As always, I will do my best to help you out.
FERRO Environmental offers a full spectrum of environmental contracting services to ensure that when you only have one chance to get it right with waste disposal, your site and your bottom-line are always protected. Contact us to learn how we can help you today!