What is Mold? – Mold can be found almost anywhere; it can grow on virtually any organic substance, as long as moisture and oxygen are present. Mold can grow on wood, paper, carpet, foods, and insulation. When excessive moisture accumulates in buildings or on building materials, mold growth will often occur, particularly if the moisture problem remains undiscovered or unresolved.
Some of the more common indoor molds are Penicillium, Aspergillus, Cladosporium and Alternaria.
Many types of molds exist. All molds have the potential to cause health effects. Molds can produce allergens that can trigger allergic reactions or even asthma attacks in people allergic to mold. Others are known to produce potent toxins and/or irritants. Potential health concerns are an important reason to prevent mold growth and to remediate/clean up any existing indoor mold growth.
Do you need to test for mold – Environmental Protection Agency (EPA) and the American Industrial Hygiene Association (AIHA) do not recommend testing the air for molds in single-family dwellings and similar buildings as a first step. The recommended first step is having a trained investigator check your house for mold.
Please understand there are NO EPA or other federal limits which have been set for mold or mold spores, sampling cannot be used to check a building’s compliance with federal mold standards. As well, air sampling can only provide a snap shot in time where mold levels can vary widely at different times and days.
A thorough investigation based on building-science principles and experience is more helpful than testing the air. An air sample test does not pinpoint sources of moisture, tell you why you have a mold problem or suggest ways to fix it. A trained investigator determines causes and suggests ways to remediate and improve potential problems. A properly trained investigator who follows a Certified Mold Investigation Procedure/Guidelines provides you with a written report that includes recommendations.
Mold Testing – Viable – Viable refers to collecting mold spores using a method that allows the spores to grow. The laboratory analyzes the samples while they are living and growing, and this allows the laboratory to accurately determine the exact type of species and genus. Generally used if a doctor needs to understand the family and species or maybe in litigation. It takes longer than non-viable testing, since seven days of culturing is required. Viable testing may not identify dead mold spores
Mold Testing Non-Viable – Mold inspectors typically use non-viable sampling in their inspections which is the most popular and least costly method. A non-viable sample is directly examined under a microscope. The mold spores are identified and counted. Other particulates are examined and identified based on a sample’s physical features, such as fibers, skin cells, and hyphae fragments. The spores alone cannot identify some molds, such as Aspergillus and Penicillium. These are reported as a group in, for example, the Aspergillus/Penicillium group or the Periconial/Myxomycetes group.
When do you test for mold?
1. Lawyers/Doctors -There may be some situations where mold testing (air and or surface) may be necessary: for instance, you are has asked for mold tests or mold investigation.
2. Building Owners – Additional reason your house or office might need mold testing, building health is one of them. Unusually high mold spore count indicates structural damage or hidden water leak or condensation.In a few cases, mold is strongly suspected but is not seen and you are not prepared to start taking walls down. The moldy odour may also be occasional and you are unsure whether mold is a problem. Testing the air may be justified.
3. During an Inspection – There are times when a surface sample is a good idea, such as when the inspector identifies a red flag, such as stains which may or may not resemble mold and you the buyer, during a home purchase, may need to understand what your next step will be, such as, provide 3rd party laboratory proof that it is indeed mold to renegotiate, back out of a deal or arrange to have it remediated (removed).
4. Attic – Probably one of the most common concerns. Typically, you will observe dark or black stains, discoloration on the inside of the attic on the wood walls. Mold can come in other colors but black is the most common. This black staining may or may not be mold. Sometimes it can be dormant which means it was mold at one point when the conditions inside the attic were ideal (high humidity) but now since it’s dry the spores may have died and fallen off. This dormant mold can still become active under the right conditions (moisture). Understanding the cause and dealing with the damage is important to consider. A licensed specialist should be consulted to understand your options.
5. Cold Cellars – Another common area – Is the cold cellar properly vented to allow warm moist air to escape? Have you packed the cold cellar with cellulose type material (boxes, paper, cloths, wood etc.). Does the cold cellar smell musty?. The cold cellar should have regulation vent holes to allow the warm moist air entering, such as every time you open the door, to circulate to the outside.
6. Basement Foundation Walls – Mold does not usually grow on brick or cement – It can grow if there is dirt and or the cement is painted. You should make sure the humidity levels in the basement are low and all water leaks are immediately improved.
7. Garages – Inside the garage on the ceiling. Is there a washroom above the garage or maybe the garage has a roof above.
NOTE: Obviously mold can grow in many other areas of your home or office. High humidity, leaking pipes and water entry into the property can and most often will lead to mold growth sometimes within 2-3 days. Make sure you deal with it immediately or it will grow and spread very quickly.
In many cases it may be obvious that the staining or suspect area is mold, especially if all the right conditions are present such as water entry or high humidity has occurred. Home Inspectors will typically report, further inspection by a licensed professional or mold specialist. You may decide to have samples taken or you may decide not to…that is your decision.
Also, please keep in mind that a conflict of interest may present itself, if the home inspector who identified the issue is also the one you are paying to have a sample tested. A qualified third party who did not identify the possible issue may be best to actually collect the sample and have it tested at a licensed lab. This is for mold and or any other issue
How do you remove mold? – Depending on the amount/size of infected area, as well, where it’s located will determine the type of removal or remediation. Some more popular ways are as follows:
1. Temporary Encapsulators or Painting – these methods may use chemicals, will they last? Hard to say. Is this method safe in all locations such as an attic and are there any indoor air quality issues with chemicals? Attics can become very hot in summer time, will the paint give off gases?
2. Blasting – A method which blasts the mold off of the surface, removing a portion of the surface but may not eliminate all of the mold and may also blow the mold particles into other areas.
3. Replacing or Removing Areas – Depending on the infected area, such as an attic, you may remove and replace the sheathing but how about the rafters and insulation?
4. Bleach or some other Chemical – Mold can be found on wood or other porous material – will the use of chemicals clean all the areas, maybe, but you may only remove the surface areas how about deep down into the material? Also chemicals may not be the best for indoor air quality.
5. Do It Yourself – In some situations you can attempt to clean the infected area up yourself. Proper Personal Protection should be considered. For more information I have provided several CMHC (Canadian Mortgage and Housing Corporation) and EPA (Environmental Protection Agency) files for your information.
DO NOT attempt to remediate yourself if you have any type of ALLERGIES/INFECTIONS/ASTHMA. Consult with your physician prior to performing any type of mold remediation.
More info on Mold
CMHC – Should You Test For Mold
CMHC – Fighting Mold
CMHC – Tenants Guide To Mold
EPA – Mold Guide
EPA – Mold Remediation