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The Mold Story

To understand mold is as simple as understanding life itself. Every single thing on the planet, including mold, needs some basic things to survive.

· Shelter (temperature)

· Food

· Water

We all live in shelters of some kind whether it be in a house or somewhere else protected. Some molds prefer to be sheltered by the layers of wall and roofing materials present in your house.

The second thing is food and for some molds, your home is the food they need to survive.

The final item is water and of the three, we can have the biggest effect on this one.

If we control the moisture in our homes, we can control what lives there.

Drywall is the main problem

The primary wall covering used in the U.S is drywall. That amounts to gypsum and fiberglass and wood pulp. The problem comes when we expose water-sensitive materials like drywall and wood products to higher levels of moisture than they can withstand. This causes mold and other things like bacteria and other types of fungi to grow.

If I were to soak a piece of drywall and a sponge in the sink for just a few minutes and leave them to dry on the sink edge the drywall will still be wet long after the sponge has dried. Drywall holds more moisture for significantly longer than a sponge.

It only takes 24 hours

It does not take long for the problem to begin once moisture finds itself on cellulose-bearing products such as drywall, ceiling tiles, or other food we call home. If a wetness incident occurs, we must react quickly to avoid expensive replacement of items before the mold can take hold.

Within 24 hours the attack is on and we need to reduce moisture levels quickly. The typical weapons are air movers/fans, dehumidifiers, and heaters. These are all used to evaporate and trap moisture.

Some things cannot be saved and are not cleanable. The most common of these things is drywall. Once the drywall is fully saturated with water, the drying time is so slow that the only way to deal with it is to remove it. This can be true of a lot of things if we don’t get them dry right away. For instance, once a piece of furniture has had mold growth on it, it must be discarded unless it can be dried in some way in a timely manner to save it.

There are experts in the remediation business who know the need for speed and can often save some of the owner’s favorite items before it’s too late. Once a water incident occurs, the amount of water will be a determining factor in what can be saved but time is everything.

Mold is like a dandelion in some ways

Although much smaller, the diagrams I see always remind me of the common weed. While this is an oversimplified discussion, hopefully it makes the point.

If the house is wet and cellulose or some plastics are available to the mold spores commonly in the air, then just like a plant in the wild, they will rest on the wet surface and produce a mold (plant). The mold will mature in about 7 days (depending on type and conditions) and at that time, like a dandelion, it will produce seeds (spores). The object of all life is to live and propagate and that is what mold will do too.

The mold spores will travel in search of new places to grow and the cycle will continue and multiply until the conditions no longer exist to grow new spores or the food source has been exhausted. In a home, the food is almost unlimited from the drywall on the walls to the OSB (oriented strand board) in walls, floors, and roof decking. Mold is very common in construction, as there is a lot to eat in a home. All those sections of wooden framing beams, trusses, and joists in a home under the right conditions provide a source of food for mold.

We as humans have decided to construct our homes of mostly mold food.

What we can do to limit the problem

Do not ignore moisture problems. If you see a stain from a roof leak or a side wall leak into the finished area of the basement, this is a serious problem and the average person knows what it looks like. You must react with speed to protect the occupants of the home.

In general, around here (mid-Atlantic) we have a wetting period in the summer and a drying period in the winter. Other areas may have different wet seasons or times. In Washington state, for example, there’s moisture year-round because they’re in a rain forest. But in Arizona, all year is a drying period, with fleeting summer storms. Wherever we are we want our environment to be comfortable, but if we use equipment in our homes that produce moisture, we need to think about how that affects the house or building we live in.

Whole house humidifiers around here are not the best idea. If we have a whole house humidifier and it is set at 45% in the right kind of house and in the right conditions, we may create mold in the wall cavity between the house and the outside. In the mid-Atlantic area, a humidifier should never be set above 30% because mid-Atlantic air already tends to be humid. In other places like Vermont, it is so dry in the winter that the moisture is under 10% which may cause nose bleeds and other uncomfortable outcomes without a humidifier. The point being- different climates around the country require different fixes. The differences in ventilation will also be affected by the climate. The climate plays a big part in mold.

A house is a tiny climate

Understand that problems in one part of the home/building can affect other areas. If there is a long-term wetness problem in a crawlspace or basement, that moisture will rise through the structure and may lead to a mold issue both in the lower level and in the attic. The ventilation system in the attic can have some moisture but a wet basement or crawlspace overwhelms the attic’s ability to remove the moisture. Simply someone in your home who takes extremely long hot showers, may be enough to tip the scales to allow a moisture build-up in the attic.

Construction may not have prevented the problem so improvements may make the home much safer. Adding a basement wetness control system, making sure the dryer vent is not leaking under the home or in the attic, and making sure the bathroom vents go outside are all things that can keep the home ventilated to avoid mold issues. If you see water standing anywhere in the home (basement/ crawlspace), you need to react quickly. This is a point raised before, but if you take nothing else away from this article, please remember that speed is priority number one with a mold problem.

Specifics: A crawlspace with vents and air conditioning

The problem is that when the air conditioning is on, the floor in the house is cold. The vents allow hot outside air to make contact with the cold floor joists and condensation happens on the surface of the floor joists below the insulation in the crawlspace. This is food in contact with moisture and because the mold spores are always in the air, this is almost always a recipe for mold growth.

There are ways to solve this problem. The most common way is to seal the vents and cover all the soil and most of the foundation wall with plastic and remove fiberglass insulation and install foam insulation against the foundation and seal everything and install a dehumidifier. The reason they call it a conditioned crawlspace is because we use equipment to condition the air. Just installing a vapor barrier in a crawlspace will help and I find less of the problem in taller crawlspaces with move volume of air in them.

Specifics: Stucco and faux stone

These materials in some ways have gotten a bad rap. Not to be funny but if it’s not wrapped/sealed properly, then that’s where the lion’s share of the problems come from. If the builder uses a wood sheathing and doesn’t add a veneer wall in front of the home/building of real stone, then the homeowner’s precautions must be correct to keep water away from the areas of the home where the damage can occur quickly. If the wall system supporting the masonry products is not protected, it will damage the wood, and then a mold problem will develop. Here again, wood sheathing in contact with moisture will develop a mold problem.

Specifics: Vent from moisture producing items

The bathroom vent and the dryer vent can do major damage to a home. If the dryer vent is not properly moving the water from the laundry to the exterior a mold problem can develop wherever the water ends up. If the vents from the baths are not extended to the exterior this can cause a moisture buildup in the bathroom and the attic. The issue for attics is the difference in temperature. The steamy, hot shower vents into the cold attic which produces condensation on the wood surfaces and creates a mold problem.

Example: I did an inspection where a premade home was set on a crawlspace and the dryer vent was drilled through the floor and was never extended any further. After about 10 years, the moisture and rot that developed had almost cut through the triple main beam. It was repaired but it just made no sense to allow a safety hazard to cause structural damage and mold. If you live on a crawlspace, you should inspect it often.

The picture to the right is a more recent example of the same issue. If not addressed this house will experience rot too.

How mold affects some people in the home but not others

The facts are best described by your doctor. I am not a doctor but I know some basic information that may help. However, if you have any concerns about your health, you should contact your doctor right away.

The need for mold testing is often driven by people in a house or building showing a negative reaction to a mysterious ‘something’.

Some people have extreme reactions to a mold that does not bother the majority of people. This is commonly described as an allergic reaction, similar in some ways to the way some people react to ragweed and others don’t. Some molds may affect us and some may not, but there is no way to know until you have been exposed or tested.

Example of how this can work:

We were called to a home where the new tenant and her family had just moved in and she had a newborn and two other children. No one in the house was showing any effect except the young mother and she was in major distress and was concerned for her life. We suggested her doctor/allergist get involved right away. We did mold testing on the house in the basement and in the master bedroom and the levels were listed as not elevated by the lab. It did show some molds, because there are always some molds, but nothing at a level that would bother the average person. The tenant was anything but average and the levels that were not bothering anyone else were putting her life in danger (Once again, not a doctor). In this case, the landlord allowed them to vacate and break the newly signed lease.

The reason we can tell you that you have a lead problem is that the government has listed that at 30 ppb (parts per Billion) you are poisoned. Mold does not work like that because every person has a different reaction. This is the time to trust yourself. If you think something in your environment is affecting your quality of life, you should try to track it down and improve the conditions. If you feel as though something in your environment is affecting your health, you should feel empowered to uncover the problem and improve the conditions.

Understanding how mold testing can help and how it works

We use a variety of testing methods:

Swab Test - This type of testing is to determine what type of mold is on a certain area and if a comparison is needed, we can take a sample in an area that is not affected and look for differences.

Tape Lift - This is similar in some ways to the swab test and is good to find out what types of mold are on a specific area.

Air Test – This type of testing is the most common and the most common testing we do. We take an outside sample as a control and at least two tests inside. Some clients choose just two and some choose to do a tape lift or swab and two air tests on the outside and one in the area of concern. If we do the air testing outside and inside, we can compare what is naturally in the air where we live. A concentration much higher inside or a mold in high concentration that does not exist outside will usually get a result of elevated mold spore counts in the home/building. We can give advice on what we found but our training is limited to testing and we stay in our lane and are not in the business of fixing houses and are simply there to help find and identify the problem.

In conclusion

If we live on this planet, we must keep the parts of the home/building we live in dry. We need to think about moisture and not be careless about the contact of moisture and wood/paper/ drywall and all other water-sensitive materials. We need to believe in ourselves when we feel something is not right. We should reach out for help before the situation changes how we live.

Fungus is 25% of the dry biomass on the planet (way more than us). We experience it every day. If you are in your favorite restaurant with a glass of wine in one hand a and piece of cheese in the other, you have mold/fungus in both hands.

If you want to escape mold, you will need to leave the planet.


Click here for more on Reliable mold testing. If you'd like to schedule a mold test give us a call today at (877) 993-9100!

And thank you for reading!

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