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Mold In Bathroom


Fighting against mold growth in homes and businesses is a constant battle. Requiring only a bit of food and moisture, molds grow quickly and spreads rapidly without proper intervention.
Understanding what causes mold in a house is key to preventing it from growing in the first place. While visible dark green or black patches may be obvious, the question of “where does mold comes from?” is a bit more nuanced.  
Often, where it becomes visible is not the same location as its source. Understanding the conditions that mold needs to grow is an important clue to determining where the root problem is. 
Professional mold detection and removal services are trained to locate the source and assist with its removal and clean-up. 
Below, we examine some of the main causes of mold in homes and where it comes from. 

The Conditions Mold Needs To Grow

Mold generally needs a few conditions to multiply and spread throughout your home or business. Since there are many different types of mold, the conditions they thrive varies from species to species. But most molds found in homes need these conditions to thrive. 


Different species of mold can survive and thrive in a wide range of temperatures from below 0 to over 40 degrees Celsius. Most find an ideal temperature between 25-30 degrees, and with a few exceptions, won’t grow in temperatures below 4.4 degrees. 
That’s why most refrigerators are set to somewhere between 2-4 degrees as many dangerous varieties won’t grow in these temperatures. Of course if you leave your sandwich or strawberries in the fridge for too long, you’ll end up with moldy food, but generally the mold will be contained and wont spread. But as long as you throw it out right away and thoroughly wash the container, it shouldn’t make you sick.    
In general, the warmer and more humid the area is, the more likely you’ll find mold. That’s why it’s important to keep your eye on areas like the bathroom, shower, laundry rooms, kitchens, attics, and basements. 


It’s easy to put off fixing that leaky faucet until another more convenient time. But often by the time you get around to it, you've already got a problem. How long does mold take to grow in the right conditions? Only 24-48 hours. That’s why you must address moisture problems right away. 
Moisture can come in the form of leaky roofs, basements, taps, poorly ventilated rooms, and moisture build-up. A good rule of thumb is to try and keep the moisture level of any space in your home to under 50%. Open up windows to promote air flow, or purchase a good dehumidifier to keep humidity down.

Food Source

Mold & Moisture
Mold is a living, breathing organism and needs to eat just like we do. What does mold eat? Well, it eats and metabolizes nearly all organic carbon-based matter. 
Some of the more common materials molds consume include wood, fabric, drywall, carpeting.


Mold prefers to grow in darkness, but can tolerate indirect sunlight and even some direct sunlight. It often starts in dark places and spread outwards, becoming visible only once the problem is quite severe.
This is an important reminder that mold often grows in places that are hard to reach. The visible, easy to reach patches you see is likely only the tip of the iceberg.  The bigger problem is often hiding behind walls, under carpet or floorboards, or in insulation.  
As annoying as it might be, try to clean out these hard-to-reach and dark areas like crawl spaces, storage, basements, and attics regularly to inspect for signs of mold. 


Most mold species are classified as obligate aerobes. They, like us, need oxygen to survive, grow, and reproduce. Not only is oxygen needed for the organic production of cells, but air supply is essential for spores to spread throughout the home. 


With the right conditions, many molds take only 24-48 hours to begin growing. This is why it’s important to get leaks fixed straight away. Once mold sets up shop, it can easily spread to other areas.
If the area of mold is over 1 square meter, it's strongly advised to contact a remediation service for professional removal.
Mold & Moisture 2

What Causes Mold to grow in Homes, apartments, & businesses?


A few days of heavy rain or high humidity can increase the chance of growth in your home. Professionals use a device known as a hygrometer to measure the humidity in a given space. The recommendation is to keep humidity levels below 50%, ideally between 30-50%. 
Not only is humidity one of the causes of mold, but it means that standing water and damp materials in the home may take longer to dry out. These wet surfaces can in turn become infected with spores as well. 

Leaky Pipes Or Leaky Roof

Leaky Faucet
A leaky roof or leaky pipes and faucets are one of the most common causes of mold growth. The most dangerous leaks are those that happen behind walls, under floors, or are otherwise hidden, often going for weeks or months before being discovered.

Condensation Build-Up

Surfaces in the home may experience a build-up of condensation, especially during the winter when temperatures fluctuate frequently. Areas such as metal piping, concrete, and walls. Anywhere condensation is building up is prime real estate for mold to grow and thrive. 

Poor Ventilation

Poor ventilation is another one of the most common causes of mold in a home. Poor ventilation leads to stagnant moist air that creates the ideal conditions for infestation. Without proper airflow, wet areas dry more slowly, which is especially risky in areas such as bathrooms, laundry rooms, basements, and attics.

Wet Clothing

Wet Clothes In Laundry
Leaving wet clothes piled on the floor creates another ideal condition. Molds not only grow on the clothes, but also on the surface they’re touching such as carpet, wood floors, and the walls.  
Try to keep wet clothing off the floor and air dry outside if possible. Drying clothes inside can create additional moisture which is one of the causes of growth.

Water Near House Foundation

A build-up of water under the house is an extremely dangerous situation if left for too long. If water is running down toward the house instead of away from it, it can pool around the house foundation causing wood rot and mold to grow. 

Mold Prevention Tips

The best defense against infestation and exposure is prevention. Here are some tips and recommendations to keep mold away from the home. If you already have growth inside your home, the first step is to call a remediation and removal company right away to test the air quality, determine the type of mold, and remove it using proper tools and safety equipment. 
Here are some of our top mold prevention tips.  
  1. Get regular home inspections
  2. Fix & prevent leaks
  3. Dry wet areas immediately
  4. Promote more airflow by opening windows and doors
  5. Use mold-resistant products
  6. Monitor humidity levels
  7. Clean your gutters of leaves & debris
  8. Keep spaces free of clutter 
Mold doesn’t have to be a problem for you and your family. Contact Mold Removal Calgary to schedule your appointment today.