Do you ever notice condensation and mold along your windows?
How about mold along the walls inside your closets?
These issues are so common that an entire chapter has been dedicated to mold on walls, floors, ceilings, windows, inside closets, and on furniture, etc.
During the cooler winter months, you will likely find mold growing on the window sills of wood and metal-framed windows.
Take a look at the water pooling along the window sill. This picture was taken in the winter. Metal framed, single-pane windows are especially problematic for mold growth.
As mentioned throughout this guide, mold needs water to grow and the condensation along the windows is just perfect for mold to grow.
Consider this… Your windows are the coldest part of the home because there is no insulation. The metal window frame cools down and begins to condensate, as the surface cannot hold moisture when it is mixed with the warmer inside air.
The same thing happens when you take a cold beverage out of the refrigerator and place it on the table. Very soon you will see water droplets form along the surface of the bottle or can.
Simply put, mold thrives on these cooler wet surfaces; the dirt and dust serve as a food source.
Vinyl windows are less problematic because they do not cool down as much as metal, yet mold will grow when there is too much condensation.
Of course, debris will build up over time in the window track, frame, and window sill.
Ceilings, walls, closet walls, or surfaces near kitchens & bathrooms may reveal signs of mold, as they are located close to moisture-producing areas.
If you cook and do not use the kitchen fan to remove the humidity, then condensation will appear on the nearby windows.
You may have seen mold along the walls of your bedroom closet, as noted in this picture.
Closet mold is common in dusty, exterior (outside) facing closets with no circulation.
Older homes, with limited circulation, can encourage mold growth because of the temperature fluctuations, which leads to condensation. Sometimes this happens due to limited or missing insulation behind the outside closet wall.
Mold in closets is common when items are stored against the wall for an extended period of time.
It is not uncommon to see mold on clothing and shoes that have been exposed to these conditions. Organic materials like leather are perfect for mold.
The soil in your houseplants is the perfect home for mold!
We know that mold grows on organic materials (dead and decaying vegetation), so it is little wonder that it can accumulate and grow on the plant-soil inside your home. Each time you water your plants, you are facilitating mold growth.
Although plants are great for filtering and cleaning the air, too many plants in one location can cause issues for those with allergies to mold, as in the example below.
During a mold inspection, a client was complaining about mold-related health issues.
I looked everywhere and was not able to determine the source of the mold. So I decided to test the air quality to determine if there was an answer to this puzzle.
After receiving the mold lab report, I discovered high mold spore counts in the living room, where the client had been complaining of allergies. This was weird, as there were no obvious signs.
Typically there are clues, such as water damage, a texture change along a floor, or mold growing on a wall, etc.
After going through the photos of the inspection report and chatting with the lab technician we discovered that there were several houseplants in the living room where the sample was taken.
Case solved! The client was allergic to the Basidiospores in the plant soil.
Regardless of the mold source, mold can easily spread to other areas of the home. The more plants you have, the more potential mold for spores to spread.
A common cause of inside mold is from drying clothing on racks, rather than using the dryer. The problem is magnified in the winter when people keep the windows closed.
The humidity from the wet clothing migrates throughout the home, leading to high humidity on nearby surfaces.
There are ways to dry laundry inside without causing excess humidity, which will be described later on in the chapter.
Fish tanks, large and small, cause excess humidity. Fish owners frequently add water to the tank, which contributes to a humid mold-loving indoor environment.
So far, we have uncovered the various reasons why mold is growing inside our homes. Next, we will uncover the best way to manage and prevent the mold from getting out of control.
What Are The Best Strategies For Preventing Mold Along Windows?
Since windows are always the coldest surface of the home, it is important to keep them warm and dry, especially in older homes.
Many homes built before the 1950s did not have heat below the windows. If this is the case, you have a few choices. You can use a space heater or install a heater below the windows.
If you live in a newer home, it is a good idea to turn on the heat to about 20 degrees as this will help keep the area warm and dry.
The mold & mildew can be cleaned off with a mold remover from your local hardware store, or with a simple green solution consisting of 1-part vinegar, 1-part dish soap to 10 parts water, mixed in a spray bottle.
If you want a convenient option, use antibacterial wipes to remove the debris from the windows, frames, window tracks, and window sills.
This will clean and kill the residual mold. Follow this by taking a cloth and drying the surfaces. Continue this routine in the morning, and especially during the winter.
Don’t use a feather duster. This will only move the dust from one location to another.
What Are The Best Ways To Prevent Mold In The Bedrooms And Common Areas?
Use a HEPA vacuum cleaner, and remove the dust, dirt, debris, and cobwebs from all surfaces - walls, floors, ceiling, and furniture (front, back, above & below). The idea is to remove dust and debris anywhere it accumulates.
All rugs and carpets should be cleaned frequently as they hold a lot of dirt and other organic debris.
Wet carpets and flooring will need to be dried as soon as possible too, because they will typically become consumed with mold, especially below the surface and into the carpet underlay.
This picture shows what happens when water seeps below a carpet and dries out. In other cases, you will see white or brown patches.
Unfortunately, in this case, the carpet had to be thrown away.
Aspergillus molds can survive on dry dust particles that accumulate and settle in your home.
Although all mold types need moisture and oxygen to grow, some mold species have proven to be quite resilient.
In fact, dry mold doesn’t really die. It sits dormant until moisture is present.
Use a critical eye to check for dust accumulation along exterior walls and corners, especially in closets with limited airflow.
Check for dark staining on the ceilings, below bathrooms, kitchens, and the attic. This picture shows exactly what surface mold looks like below the attic.
This surface mold can be cleaned off with the “green” solutions mentioned above. Textured ceilings are more difficult to clean without changing the look of the ceiling.
However, if you are patient, you can remove the surface mold by first spraying the area with the green solution I mentioned.
Wait for a ½ hour and then saturate a disposable cloth with the same solution and dab it until it is clean.
If your time is better spent with other tasks, call in a mold removal company to help you.
When storing items in the closet, it is best to place them an inch or two away from the walls to allow for proper airflow and circulation. This rule applies to furniture as well.
What is the best way to reduce indoor humidity?
To get an idea of how much humidity you have in the home, you can buy a hygrometer from your local hardware store.
This inexpensive device measures the relative humidity and temperature in your home. Here is an example of one.
If you live in a home with a lot of humidity, you can combat that by using a dehumidifier. In addition to a dehumidifier, you can also purchase moisture-absorbing products.
They cost less than a dehumidifier, and fit great in smaller areas like closets, under stairs, in bathrooms or laundry rooms, etc. You will have to replace them, so read the label to soo how long they last.
When the weather is warm and dry, open the windows on opposite sides of the home to promote cross-ventilation and fresh air exchange. All you need is an inch to achieve this.
However, it is not advisable to open the windows during the winter, or when it is raining or foggy outside. You want to prevent moist air from coming into the home.
If you have the budget, consider installing an HRV system. This unit removes the older, warm stale air from the home while exchanging the excess heat with the newly introduced cooler air through a filter as it enters the home.
Most new homes will be equipped with one. HRV units keep the air fresh and help maintain the better overall air quality in the home.
And with any appliance, they need to be properly maintained to prevent indoor air quality issues and possible mold. Be sure to have the system properly inspected annually and all filters cleaned every few months.
The condensate line (where accumulated condensation escapes) can become clogged and plugged, so it will need to be checked and properly set up as well.
If you have plants in your home, it is best to limit the number to a few in each area, especially if you have mold allergies. Consider replacing a number of your plants with a few cactus plants.
This chapter concludes Mold Insight's Guide to Mold prevention.
I hope this information has been a helpful resource to you for understanding mold and the best ways to remove and prevent it from coming back.
For a list of the most recommended products to help you prevent or remove mold, check out this Resource page.