6 Common Causes of Mold

mold coating a ceilingMold Can Be A Serious Health Risk

Alpine Cleaning, a company that handles many different forms of cleaning and restoration projects in Utah, told us recently that they’ve been seeing an increase in cases of mold. Mold can be a serious health risk. Some people have allergies to mold, while certain types of mold produce spores that are simply toxic when inhaled.

What Mold Needs

Mold is an organism, specifically a type of fungus. Like all organisms, it needs a few basic things to live. It needs a food source, which can be anything from human food left out in open air, to porous substances like paper, wood, drywall, and cotton. It needs water, as all living things do in some capacity. It needs warmth: temperatures below 50 degrees inhibits mold growth. Ultraviolet will kill mold, so it needs a dark place out of direct sunlight. Finally, it needs time: mold grows fairly slowly. If mold spores reach a location that has these requirements, it will begin to sprout, invisibly at first, but slowly forming larger colonies.

Mold Is Hard To Kill

Often by the time mold has grown enough to become visible, it’s already deeply rooted in the material it’s growing on. Such materials frequently cannot be cleaned because of this and must simply be thrown out. If mold infests the drywall of your house, this often means needing to tear down the wall in its entirety and replacing it. This can be expensive, so the best way to deal with mold is prevention. In order to prevent it, however, you first need to know what causes it. So, here are the most common causes of mold.

1. High Humidity

Since mold needs moisture, excess humidity is easily the most common cause of mold. In some places, high humidity can be responsible for up to 70% of reported cases of mold infestation. Here in Utah, where the air is usually hot and dry, natural humidity reaches levels required to start a mold infestation far less often. Instead, we often see mold starting in bathrooms due to water vapor from hot showers building up on walls. This can be especially true in winter, when we want to take extra warm showers and the cold walls and air make it condense much faster. To prevent this, you need to make sure your home has adequate ventilation, especially in bathrooms.

2. Poor Ventilation

bathroom exhaust fanSpeaking of, poor ventilation is another major contributing factor to mold infestations here in Utah. There are many rules in place that require adequate ventilation, but in some places, some companies may attempt to slide the rules because they think the dry air means it’s less of a problem. In reality, the opposite is true. Poor ventilation will lead to stagnant air. There is always some air flow in your home and if poor ventilation creates stagnant air pockets, any moisture in the air will be moved to centralized locations. Even if the air isn’t very humid, it builds up over time, eventually reaching levels that can sustain mold growth.

This is why building codes very strictly insist that ventilation systems should not vent into attics, or crawlspaces and should vent at least 3 feet or more from any openings to a house. If you’ve had recurring problems with mold, check your ventilation system to make sure it follows this code.

3. Leaks and Floods

Mold often sneaks up on you because it waits for a slow build up of condensation for its moisture. Sudden increase in moisture will work just as well, though. If a pipe bursts, or your roof leaks, or a flood washes through your home, all that moisture will be perfect for starting mold infestations. In the case of floods, this is very obviously a risk, but leaks in pipes or roofs aren’t always obvious. You should have your home inspected for leaks to avoid this.

a pair of shoes splashing in the mud
Photo by Jean-Daniel Francoeur

4. Damp Clothing

Cotton is a particular favorite food source of some types of mold. During the warm summer, getting caught in the rain and not drying out your clothes right away will provide all the moisture mold will need to take root. Mold only needs 24 hours to start growing in damp clothes, so make sure you never leave damp clothing to sit. Wash and dry it immediately.

5. Air Conditioning

Air conditioning is practically a requirement to get through the hottest months of summer here in Utah, but in addition to poor ventilation, it can cause mold in another way: leaking fluid. When air conditioning fluid leaks, it often becomes a breeding ground for a type of mold called Mucor. Mucor is a type of mold that builds up in white patches and is highly allergenic to humans. Check your air conditioning unit to make sure it isn’t leaking or building up moisture.

6. Damp Foundation

Water always runs downhill, drawn by gravity to the lowest point by the quickest method. If your home is built on a slope so that water flows towards your house, it can leak into your foundation. This puts you at high risk of mold building up in the foundation of your house, which can spread to other areas from there. To fix this, you’ll need a landscaping specialist to fix the slope of your yard.

Do Not Delay With Mold

Mold may take time to grow and even more time to reach levels that are visible to the naked eye, but once it takes root, it is fiendishly difficult to get rid of. You should never delay dealing with even the conditions that cause mold. If anything in your home gets damp, you should dry it immediately. If you find leaks, fix them as soon as you do. If you find moisture condensing in your home, find the cause and correct it. If you leave it sitting long enough for mold to take root, chances are high that you’ll end up needing to throw out the infected substances, which may require replacing entire walls in your house.
Given the health hazard mold – especially toxic mold spores – can present to human health, you should never take a chance on infections. Prevention is the best way to combat it, so take every precaution you can.