Mold Is Good
Mold is what makes nature’s cycle complete. The role of mold is to break down the energy in plants/cellulose so that it can return to the earth, beginning its cycle all over again.
Our society has decided that it makes good sense to build our houses out of trees. We frame them with sticks of wood, sheath them with plywood and OSB (shredded wood mixed with glue + heat), and finish off the inside with sheetrock that is faced with paper on both sides. Even though we live in houses made of mold food, mold food is only appetizing when moisture levels are out of balance. Since we can’t easily eliminate mold food from our houses, it becomes very important that we keep them dry.
Three Main Moisture Sources
Plumbing leaks:
Typically a result of freezing. The only way a pipe can freeze in a house is if it’s located in an exterior wall cavity that is poorly insulated or in a cavity that is connected to outdoor air via breaks in the air-barrier. When planning the location of plumbing, consider the temperature of the cavity where the pipes are located. Interior walls and well-sealed floor cavities are the best options. When positioning water heaters or air-handlers on upper levels, include drain pans beneath them to prevent damage should (when is more realistic) a leak occur(s).
“Outside” moisture: from the sky, from the ground, and from the air
Water from the sky should go exactly where you want it to go – away from your house. Leaky roofs/flashing details, negative slopes around the house (land sloping toward your house), missing drainage planes between the sheathing and the siding, and non-functioning gutters are typical “sky water” problems seen in the field.
Water from the ground should also be managed by design. The lack of vapor control systems in the crawlspace and poor (or non-existent) exterior foundation drainage systems are common “ground water” intrusion problems.
The most mysterious of the three is moisture from the air – vapor. Vapor gets into the home via air leakage or by diffusing through each material that composes your building envelope (walls/roof/floor). Air leakage transports about 100 times the amount of moisture from outside to inside than does the natural diffusion of vapor through the materials in the wall. So, if you’re concerned about moisture, you need to control the air leakage.
Outside air that leaks into your home through the building envelope carries moisture into these cavities. If these cavities contain wood, darkness, and the right temperature range, you have perfect conditions for mold growth. In the summertime, outside vapor wants to move into the house (moves from high levels to low levels). In the wintertime, the opposite is true. So, the likelihood of mold growth is pretty high when outdoor air can leak into the wall cavities and condense on the back of a cold piece of sheetrock (air conditioned house) that is lined with paper. This is also a problem if there is a layer of plastic between the sheetrock and the studs. Now, the condensation will drip down the plastic and settle in the bottom of the wall. The same can be said in the winter. But, the cold surface is the outer surface of the house – the sheathing. The only way to control this air-transported vapor is to seal the holes in your walls which, like most things, is easier to do while the house is being built.
To battle outdoor moisture, the house should be as air-tight as possible and be designed to shed water. There are many materials and systems that play a part in the control of moisture. There are exotic materials that are simple to install while there are simple materials that require more careful installation. Either route will work, as long as the building envelope is functioning as a system. Investing more energy/money in controlling moisture within the building envelope will be well worth the effort in the long run.
Moisture produced inside the house:
Indoor moisture should be removed with proper use of bathroom/kitchen exhaust fans. It is imperative that these ducts take the exhausted air all the way to the outside, not just into the attic. It is also important that the ductwork on these fans be as short as possible with very few bends. If you cannot avoid a long duct run, get a larger fan or install a booster fan to compensate for the added static pressure.
Right-sized Air Conditioners
Oversized air conditioners (A/C) are also quite common and can create high moisture levels inside the home. First, understand that an A/C’s role is to cool AND dehumidify. When an A/C unit is too large, it satisfies the temperature demand of the thermostat before it has the chance to remove enough moisture to make the house comfortable (this requires longer run times). All you’re left with in this scenario is cool/sticky air, high moisture levels, and lots of cold surfaces. Remember, bigger is not always better.
What size is the right size? A “Manual-J” calculation can be done to determine the proper sized machinery for your specific house. This calculation is generated by using a sophisticated computer software program, which takes many different variables into account, all of which are specific to your house. This report not only tells you how big the overall system should be, but also how much air to inject into each room of the house for optimum comfort.
No one wants a rotting house that stinks of mold. A true sign of a quality house is one that handles moisture properly. Whether you’re trying to improve your property or building a new home, focusing on moisture control should be a top priority for your health and your wallet.
Household Mold Issues
A typical mold will be about 10 microns (0.0002 inches) in size, and can grow anywhere there is sufficient warmth, food, and humidity in the air to absorb moisture. Any organic material, including dust, fabric, wallpaper, wood, and paint, all provide more than enough nourishment to keep mold healthy and growing. As a matter of fact, the Journal of Property Management reports that one square inch of drywall can contain 1 to 10 million spores as small as 1.5 microns in size! There are more than 1.5 million species in existence, and some molds grow only in the home. Mold grows year round in any home - no matter how clean. and according to Human Ecology, fungus consists of an estimated 25% of the Earth's biomass.
As mold matures, it begins to reproduce, sending seedlike spores out into the air. As long as the temperature is above 40 degrees Fahrenheit, they can land, grow, and spread. Time magazine reports that there can be hundreds of thousands of mold spores in a single cubic meter of air indoors, and a single person inhales 10 or 12 cubic meters each day.
Unfortunately, even you have mold only in the basement or crawlspace, its spores will rise throughout the home. The reason for this is called the "Stack Effect". Because of the stack effect, warm air rises in the home and exits through the upper levels and attic. As it does, a vacuum is created on the lower levels which draws air upwards from the basement and crawlspace. Anything in that air, including mold spores, humidity, dust mite feces, and odors, will be drawn into the main area of the home where you breathe.
Cleaning and removing crawlspace and basement mold with bleach or biocides is only a temporary solution. Mold remediation of this type can eliminate mold in the short term, but unless the reason that it was there in the first place is eliminated, there’s nothing stopping house mold from returning. To worsen the situation, Human Ecology magazine reports that dead mold can still cause allergic reactions as well, and microscopic mold spores that were not removed can lay dormant for years while they wait for the opportunity to grow. Additionally, while mold resistant coatings may keep mold off the surfaces they contact, mold will still have a surface to grow on unless you can also coat your ventilation ducts and every piece of organic material that enters the house.
Get Rid of House Mold Before it Starts
Mold will grow anywhere where it can find moisture, warmth and food, and mold will grow on anything organic in the basement.According to Total Health magazine, household mold growth is accelerated by warmth and high humidity- especially in the basement and crawlspace. Mold spores can affect a home’s inhabitants through inhalation, ingestion, and skin contact. As they do, all the symptoms of allergic rhinitis can occur, including a runny nose, watery eyes, mild allergic reactions, a scratchy throat, fatigue, and general discomfort when breathing. In rare cases, mold can even be toxic! The American Lung Association reports that 88 million people in the United States suffer from some sort of respiratory distress, and 50% of homes have at least one person living inside that has allergies, asthma, or another respiratory ailment.
The Journal of Property Management reports that ignoring a mold problem will not only lead to the compromised health of the occupants, but it can also lead to expensive home damage. Repairs can be lengthy and extensive, and in extreme cases, they may necessitate relocation of all inhabitants while the work is being conducted. Mold can grow anywhere there’s moisture, including near plumbing leaks, leaking roofs, and especially in wet and damp crawlspaces and basements. Household mold is a significant problem that has been largely ignored for too long. If there is a water problem within the home, it’s extremely important to fix the problem and dry the area within 48 hours. If there’s less moisture, there’s less mold. With less mold, there’s less damage to the home.
A Dry House is a Mold-free House
The easiest way to prevent household mold, and one of the primary methods recommended by the Environmental Protection Agency, is to reduce indoor humidity within the home to below 60%. They also recommend removing all sources of water leakage within the home, sealing penetrations in walls and floors especially below in below-ground areas, checking for moldy odors, and removing all sources of freestanding water.
Home Energy Partners is dedicated to helping eliminate basement mold and moisture. Our inorganic products are designed to form vapor barriers on the basement walls and floors to keep humidity from seeping through. Additionally, our SantaFe Basement Dehumidifier is capable of filtering the air of particles as small as one micron! This means that house mold spores, dust mite waste, pollen, and many other home environment allergens will be safely removed from the air. With its self-draining system, the Energy Star rated SantaFe is able to pull moisture from the air and lower the relative humidity below 60%. These low humidity levels create an environment that is too dry for house mold and dust mites to thrive. Thus, the area is cleaner, healthier, and more sanitary for your entire house!
