5 Easy Ways to Test for Mold in an Apartment

Exposure to toxic mold in an apartment can cause various health issues.

Mold is an environmental hazard that can lead to serious health problems if not addressed immediately – such as asthma, skin infections, nausea, and headaches.

Mold removal in an apartment can be expensive.

This is why before moving into an apartment, you need to check for mold infestation.

How to Test for Mold in an Apartment?

In this blog post, you will learn some of the ways you can test mold infestation in an apartment.

1. Visual Inspection

A mold infestation can be detected through a basic visual inspection.

One effective way to detect mold infestation is to take a sharp object such as a knife and poke it on the surface where you suspect the mold infestation to be growing, such as in the bathroom and kitchen.

A wall without a mold infestation will remain firm. It won’t get damaged when you poke the surface gently with a sharp object.

You can also detect mold infestation by touching the wood surface. If the wood surface feels soft and crumbles upon touch, it indicates a mold infestation. This shows that the mold has set in and the rotting process has started.

Discoloration of the walls and floors also indicates the presence of mold. You should keep an eye out for brown, black, or green spots. Some mold infestation appears like a water stain on the wall or floor.

The discoloration is due to the mold hiding behind the surface.

2. Strange Smell

A musty odor is the foremost sign of a mold infestation. If you detect a wet smell from the building material, it indicates that the mold may be present in the building.

Mold spores emit volatile organic compounds that have a wet, musty odor.

Most mold remediation experts will trust the nose when they walk into a building. They have a keen smell and can smell mold straight away.

It’s possible that the smell may be due to something else, but it’s still a good idea to investigate further for mold if you find any weird smell in the place.

3. Water Leaks

Water damage is a clear sign of a mold infestation. If you see the ceiling or drywall cracking or bubbling out when you apply light pressure, it indicates water damage with a strong possibility of a mold infestation.

Moisture can get trapped inside the wall due to a pipe leak. Since mold requires moisture to grow, it tends to grow faster inside the walls than on the surface.

You should look for leaky pipes inside the apartment. The two most obvious places to check are the kitchen and the bathrooms. If you detect a leaky pipe, you should check if there are signs of mold infestation near the pipe.

Note that the mold growth will not necessarily be near the leaky pipes.

Moisture tends to travel far depending on the type of material. So, look for mold infestation a few inches or even a few feet away from the pipe leak.

4. Health Issues

Mold infestation in the apartment can also be confirmed if you experience any health issues when inside the apartment.

If you experience any of the health problems below, it indicates the presence of a mold infestation.

  • Do you feel fatigued when inside the apartment?
  • Do you constantly sneeze and have watery eyes inside the apartment?
  • Do you see skin rashes after moving into the apartment?
  • Do you experience a headache whenever you are inside the apartment?

All of the above symptoms can indicate the presence of mold infestation inside the apartment.

Some people experience mild symptoms while others may experience serious complications due to mold infestation.

While this is not a confirmed way of testing for mold, in case you feel these issues, it may be an indication that you should check for mold.

Additionally, the health issues may become evident immediately for some people while it develops over time for others.

5. Use a Mold Test Kit

Mold infestation can be of different types and colors. Once you have detected telltale signs of mold, you should use a mold test kit to confirm if the mold is present in the apartment.

Mold testing kits can be used on surfaces such as walls or floors to detect an infestation. Some testing kits can also be used to detect if mold is in the air that you breathe.

The testing kits are available in most local or online home improvement stores. The kits are not that expensive; you can get a mold testing kit for $20 to $50.

Here are the steps that are typically involved in using a mold testing kit to detect the presence of mold in the apartment.

Step 1

Close the doors and windows of the room you will be testing about a day before the test.

This is important as it will allow the mold spores to congregate and stay on the surface.

Closing the door will prevent the spores from dispersing due to drafts.


Remove the kit from the package. Most kits come with a glass or plastic dish. Moreover, you can find a lid and labels along with the testing kit.

The petri dish is treated with a special microbial culture to promote the growth of mold. This will help you quickly know about mold infestation inside the apartment.


Gently remove the lid of the petri dish. You should place the dish with the open end in the upward direction on a smooth and flat surface.

Leave the petri dish at the spot for about two days. The time may be slightly different for some kits. Restrict flow in the area where the dish is placed.

This is important to avoid disturbing the air.

You should consider covering the doorway using a painter’s tape if necessary to remind guests and household family members that the area is off-limits.


Put the lid on the petri dish after a few days. Look at the manufacturer’s instructions to find out the recommended days after which to cover the dish with the lid.

You also have to put tape at the layer where the lid meets the dish. Electric tape or scotch tape will be adequate for sealing the lid.

Avoid duct tape since it is difficult to remove. You can use any tape that is easy to remove so as to avoid disturbing the petri dish.


Write a date on the petri dish and store it in a dark spot. Most kits come with labels that you can attach to the bottom of the dish.

After affixing a label, you should place the dish in a closet shelf, dresser drawer, or any other dark spot.


Inspect the petri dish after three days to see signs of mold growth inside the dish. A mold will look fuzzy and may be white, black, brown, or orange color.

If you don’t see mold growth inside the petri dish, you should return the next day to check for mold growth.

In case there is no mold growth after five days of placing the sample in a dark spot, you can throw away the dish as mold infestation is not found in the room.

Step 7

If the testing kit shows the presence of mold, you may want to send samples for lab analysis as recommended by the manufacturer to determine the type of mold infestation.

Most testing kits come with an envelope along with the mailing address, which allows you to send the sample for analysis.

Lab analysis that costs between $40 and $70 will take a few days. The report will show whether the mold infestation in the apartment is toxic and if it may cause health problems.

You will want to test for mold spores in different rooms of the house. It will require purchasing additional testing kits from the online or local store.

Difference between Mold and Mildew

When it comes to testing for mold infestation, it is important that you know the difference between mold and mildew.

Both of them are an unpleasant sight in a building, but mold is likely to cause more damage than mildew.

Mildew is a fungus that is often grey and powdery in appearance. You can easily clean the fungus using a household cleaner or elbow grease.

Mold on the other hand has a fuzzy appearance and comes in different colors such as orange, green, black, brown, yellow, purple, pink, or white.

Unlike mildew, mold grows inside the material that is why getting rid of a mold infestation is difficult and costly.

It requires the removal of the infected portion of the floor or wall with a new one.

Dealing with mold infestation promptly will reduce the risk to the health, and also reduce the extent of damage to the property.

The Bottom Line

Mold infestation won’t set off alarms like carbon monoxide or fire.

The problem usually lurks in hidden places and continues to grow undetected. The tips mentioned in this blog will help you test for any mold in an apartment.

Mold is a serious issue that should not be ignored. Apartments exist as interconnected units with common plumbing and ventilation systems.

This means that if there is a mold infestation in one unit, it can easily spread to other units in an apartment.

You need to call the apartment owner to get the mold infestation resolved as soon as possible. Letting the mold grow undetected may result in losing the damage deposit.

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