What are the 5 Biggest Mistakes Mould Inspectors Make And How To Avoid Them

Mould inspection is a process that determines if there is a problem with the home. The mould inspector will measure the humidity such as relative humidity or absolute humidity, moisture levels and then take laboratory samples to confirm the presence of mould. Mould inspectors should also be doing moisture level measurements on building materials and even use infrared cameras to look for temperature differences.

Mistake #1 – Measuring humidity when windows and doors are open

If you are measuring the humidity of your home, make sure that the windows and doors are closed. This will give you a more accurate reading of what is happening inside the home.

The humidity level in your home is determined by many factors, like how often you open your windows or doors. If you leave them open, it will equalize the humidity with that of outdoors and not give you an accurate reading of what is happening inside. If your mould inspector measures temperature and humidity when your doors and windows are open, then the measurements are meaningless.

Pre-purchase/Pre-lease inspections are often problematic because real estate agents will usually come in earlier and open the doors and windows to remove any unwanted smells.

Mistake #2 – Inspecting the home when it’s raining

Inspecting the home in the rain is not recommended. Rain can settle mould spores and increase humidity, which makes it harder to determine any moisture issues inside the home. It’s pointless to even conduct an assessment when it’s raining. Reschedule the assessment for a sunny day. Cloud days are fine too.

Mistake #3 – Failure To Conduct A Visual Inspection Of The Building

A visual inspection is a quick and inexpensive way to identify potential issues with a building. It can help you identify any major structural problems, as well as other issues that might not be visible from the outside.

Inspections are usually conducted by a professional who will walk around the building, looking for any obvious signs of damage or deterioration. They may also take photographs of the exterior of the property to make sure that there are no cracks in the walls or windows, and check for any signs of water damage. The mould inspector should then use his moisture meter or hygrometer to verify if there is a problem. For example, blocked eave gutters can overflow into the eaves and fascia, causing dampness. This can be verified by the moisture meter.

The cost of an inspection can vary depending on how big your building is and what kind of inspection you want done.

Mistake #4 – Failure To Use a Moisture Meter or Hygrometer

Moisture meters and hygrometers are essential tools for mould inspectors. They help the inspectors measure the amount of moisture in a building and when to take action.

Moisture meters measure the amount of moisture in a building, providing a reading in percentage (%) of wood moisture equivalent (WME).

Hygrometers measure the humidity levels in a room. Relative humidity is the amount of water vapour present in air compared to what would be present if it were saturated at 100%. Absolute humidity is the weight of water vapor per unit volume of dry air.

The visual inspection identifies a potential problem and the moisture meter and/or hygrometer can verify the existence of a problem.

Mistake #5 – Neglecting To Take Laboratory Mould Samples to confirm the presence of mould

Mould inspection frequency is not always the same for every home. The number of lab sampling should be based off the visual inspection and moisture/humidity measurements conducted. The mould inspector should have a theory of where the problem lies and what type of sampling should be conducted.

It is always recommended to do laboratory sampling for mould. It’s the only way to verify the existence of mould in a building. A mould inspector verbally confirming the presence of mould without proper laboratory analysis by a Mycologist is just guessing.

Laboratory analysis of air samples should always have a control/baseline sample to compare against. This is typically the outdoor sample from the front or back yard. Sometimes, 2 outdoor samples may be taken if vegetation and environment is very different from the front or back.

Surface sampling will typically occur when there is visible organic growth and may even be verified as biologically active with an ATP meter.

Pre-purchase/Pre-lease inspections are often problematic because real estate agents will open the doors and windows, which will prevent the mould inspector from taking any laboratory samples or hygrometer readings. Therefore, surface sampling or dust sampling may be the only option for confirming the presence of mould.

In conclusion, make sure you get a qualified mould inspector that knows how to conduct a proper mould inspection. It should never happen when doors and windows are left open or when it’s raining. They should be able to explain the measurements they’ve taken and have a working theory before they start to do laboratory sampling. Laboratory sampling is always recommended to verify the presence of mould. Unless the mould inspector is also a qualified mycologist with a laboratory microscope to examine the mould spores and filaments, then they are only speculating to the presence of mould. Pre-purchase or pre-lease inspections are always problematic for the mould inspector, so talk to the real estate agent to get a private inspection where the home is closed up for as long as possible.