Attic Mold Removal Causes Prevention & Cleanup

Attic Mold Removal

The attic is one of the most common areas for mold growth, and most people don’t find this out until they are trying to sell their home, upgrade their insulation and are informed by the home inspector or insulation installer. We can help by safely removing the mold in the attic and correcting the source of the cause permanently and guaranteed. Clearance certificates and guarantees will ensure peace of mind to the owner and buyer.

We not only remove mold in the attic in Toronto, Mississauga, Oakville, Burlington, Hamilton but also offer free attic mold inspections to determine the cause and provide a permanent solution.

Just to make sure we’re on the same page, if your attic looks like any of the following pictures, then it is mold specifically cladosporium growth due to condensation/moisture.

Before and after attic mold


Before and after attic mold

Below I will go through some causes and common questions we get regarding mold in the attic.

Call for your free attic mold inspection!



Causes of mold in the attic

water damage and excessive moisture causes mold and this is no different in the attic. Most of the time, condensation occurs in your attic due to ventilation issues which in turn causes leaks and moisture. This causes mildew, wood rot and interior water damage. Over time, mold grows and if left untreated, it becomes a big problem if not dealt with.

The image below illustrates the problem on the right, with the ideal house on the left.

winter attic conditions

Every house was built with a specific roof ventilation calculation to ensure adequate air ventilation. Sometimes, homeowners will add new house features such as installing bathroom exhaust vents or upgrading the insulation. These changes will affect the air circulation and create the moisture for attic mold to start rotting your roof sheeting.

attic mold


I purchased a home and my home inspector found mold in the attic, is it dangerous? what should I do?

Attic mold is the cause of a deficiency on the ventilation of the attic, depending on the extent it can be easily corrected and return the wood into new condition. In some rare and extreme situations the only solution is to replace the roof sheeting. Lets face it no one goes into the attic so most people are an ware that this condition exists. In fact the condensation that creates the attic mold only happens in very cold days and not year round. Both buyer and seller can address the issue by fixing the source and remove the mold using a specialized mold remediation company like ours.

I am selling my home and the buyers inspector found mold in my attic, what should I do?

Its not your fault, we understand, no one checks their attic unless there is a problem, and everyone would have corrected if they knew. Most often what happened is that a contractor you used advise you wrong, didn’t do their job properly or out right lied to you. We can find the cause and correct it, remove the mold permanently and provide you with a transferrable guarantee and clearance certificate so you and everyone involved can have peace of mind and know that the problem has been dealt professionally and sleep easy. Give us a call its a free inspection with no strings attached.

What happens if I don’t remove the mold in the attic?

The attic mold is the effect of attic condensation (excessive moisture). Over the years mold will decompose the roof sheeting from the inside causing undulation on wood (roof warps no longer straight) and premature shingle wear. Most roofers when replacing shingles describe it as softness of wood as they walk since they cannot see the mold growth on opposite side of sheeting. It’s hard to sell or get insurance to any home that contains mould, our advice is to remove it sooner than later.

Roof Warped Due To Mould

What’s the cost of removing mold in the attic?

Every attic and roof are different in terms of size, construction, and mold damage. The majority of companies that offer attic mold removal services in Toronto and Gta charge between $3.50 and $4 per square foot, however since all attics have different amounts of mold and degradation in the roof sheeting is not fair to you to be priced per square feet. You should be able to pay less if the extent and severity is less than the entire attic. You also need to address the cause of the mold growth to ensure it will never return. This is why we offer free inspections, so you can make an informed decision.

We offer a transferable guarantee to the property so that everyone is assured that the problem will never come back.

If you’d like an exact quote, call us now at 647-496-0860 and you’ll be put in touch with an attic mold removal specialist.

How Long Does attic mold removal take?

Depending on the severity and extent of the mold in the attic, typically it takes one day. We have corrected and permanently addressed attic mold in more than 2500 attics in the GTA in one day.

Which method do use for mold removal in the attic?

We use all methods that are cost efficient for the amount of mold and situation your attic is currently in. All attics spaces have different roof peaks, amounts of insulation, amounts of mold and extent of roof sheeting damage that’s why is imperative to perform a visual inspection of the mold in your attic. We can use dry ice, soda blasting, peracetic acid and environmentally friendly products it just depends on your situation. Below is an example of dry ice blasting a older technology when removing attic mold.

My roof sheeting is discolored is that mold?

if it looks like the pictures above, it is. Most common mold species found growing in the attic are Cladosporium, and also Myxomycetes when really bad.

I found mold in my attic is it dangerous? Do I need to leave?

No, mold in the attic will not cross contaminate other areas unless agitated and carried downstairs by attempt to remove without proper procedures. The attic ventilates outside through your roof vents therefore any mold spores will go out not inside f your bedrooms. in fact air quality testing in rooms bellow can’t find the mold that might exist in the attic.

Mold is visible in my attic do I need to test it?

No, Our Canadian guidelines indicate when mold is already visible in the attic, there is no need of testing since it will only confirm what already is visible. Example (no need-to-know what type of mold is in the bread before disposing of it) You must always remove the mold and correct the source and cause to avoid mold re occurrence.

I have children do I need to leave the home when attic mold is being removed?

No, A professional attic mold removal company will have all the remediation procedures require not only to safeguard all occupants but also their employees. Containment, negative pressure and Hepa equipment is some of the equipment used to ensure no cross contamination to other areas while removing the attic mold.

The CleanFirst Guarantee

We are so confident in our ability that we offer a transferable guarantee to the property. This is not a warranty; this is a guarantee with no strings attached that you will never have mold growing again in the attic.

Sell Your Home with Ease

With the transferable guarantee in place, you can rest assured that the buyers and home inspectors will be pleased and refilled with confidence, allowing the transaction to go through with ease.

We will remove the mold safely and permanently by restoring the original roof ventilation calculation and addressing the moisture issue that resulted in mold to start decomposing your roof sheeting.

Who we are

We are the leading Toronto mold removal company for the past 32 years with the mission of restoring the peace of mind of our customers when it comes to mold, asbestos or any environmental issue.

A simple call to 1-800-520-7443 will get you an experienced attic mold removal specialist that will give you peace of mind to you and the buyers by effectively and permanently correct and solve the attic mold.

City areas we remove mold from the attic

Toronto, Mississauga, Oakville, Burlington, Mississauga, Scarborough, Markham, Pickering, Vaughan, Hamilton, Orangeville, Brampton, Milton, Georgetown Give us a call if not listed and you need our help


“Our experience with CleanFirst was one of the best experiences we have ever had with a contractor… Early in the process, it became obvious that we had selected the correct contractor to perform the repairs to our house. In this day of corporate greed, lack of trust and meaningless goals and poor service it was very comforting to find a company that will do as they say and follow through for the customer as Cleanfirst had done for us. In hindsight, the hardest decision we had to make on the repairs of our house was selecting the contractor to represent us and perform the repairs on our house. We are very thankful that we chose CleanFirst and we would highly recommend them to others based on the positive experience we have had with them.”

– Mario F

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What our Clients Say

  • 5 out of 5 stars! After our loss and dealing with other contractors we were so scared, but you really showed us that there are still good contractors out there. Thanks again! You guys did a great job and thank you for all the extra drywall repairs your crew did....
    Mari Altomare
  • Restoring your peace of mind what an understatement. I was so scared after having the home inspection and after calling other contractors. You educate us and fixed the issue and we didn’t even have to move. Your crew is fantastic and did a great job, you really have nice people...
  • Hi Luis, thank you again for your help on the mold removal, your crew were so helpful to us and did a fantastic job. We forwarded all the information to the real estate agent and were able to sell the house. I will definitely recommend you and your services.
    Julie and Nick

Locations We Serve

Here is a list of popular locations we serve. Call us if yours is not on the list!

Ajax, Aurora
Bancroft, Barrie, Brampton, Burlington
Georgetown, Guelph
Markham, Midland, Milton, Mississauga
Newmarket, Niagara-on-the-Lake, North York
Rexdale, Richmond Hill
Scarborough, St Catharines
Waterloo, Whitby

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