How to test your home’s air for mould

Just because you don’t see mould stains you can’t assume your house is mould-free. Learn how to detect it the right way.

It comes as no surprise that Health Canada recommends that mould in a home needs to be removed. However, unless you see a surface mould stain, the fungus can be hard to detect. Helpfully mould can be identified through air testing quite easily.

• To identify the species
• To help pinpoint where it may be growing, especially if hidden
• To gauge your home’s overall air quality

The budget-friendly option is to collect samples yourself. You’ll need to buy a home mould air test kit and then send your samples to a lab that does tests for the public. The lab will send you the results in a few weeks.

A key step in collecting the samples is to be thorough. The amount of mould particles or spores in the air can vary depending on the time of year, time of day and the weather. The amount can even vary depending on the location in your house. With its moist air, the bathroom is particularly susceptible to mould growth.

As a result, you need to take air samples from multiple locations and different times. The more samples taken, the more complete the picture the lab can produce.

A strong hint that you may want to test your air for mould is if you catch a whiff of mould’s tell-tale stink.

Tracking mould can be tricky. If the air test comes back with strong readings in a certain room, but no mould is visible, it may be growing behind a major appliance, inside a wall or under a carpet. However, outdoor mould could also simply be blowing through it.

In particular, you’ll want the air test to indicate whether you have the so-called toxic black mould, Stachybotrys, or the lesser-of-evils Aspergillus. Either one can cause health problems to family members, especially young children or the elderly, whose breathing may become exacerbated by allergic reactions.

For people at risk of allergies, testing the air can help rule out mould as a trigger. Perhaps their allergies are instead being caused by animal dander or household cleaning products. Mould can be ruled out.