I recently watched a Science Channel program called Afterlife: The Strange Science of Decay that chronicled exactly what was going on as food decays over the course of about two months. (It’s a rather fascinating program that I suggest you watch if possible.) What struck me while I watched was how amazingly invasive mold fungi are.
As you probably know, mold is already in your house. It’s in your food. It can lurk in your basement, exterior walls, carpet, concrete, and definitely the shower. It’s probably in you, though I can’t substantiate that claim. Mold–or, more precisely, mold spores–are everywhere; they just lying around and waiting for conditions to be favorable… to attack! The thing is that it doesn’t take much of a change in a mold’s local environment for precisely these favorable conditions to exist.
Why is Mold a Problem?
Understand that exposure to mold is a health risk. The CDC states that “Some people are sensitive to molds. For these people, exposure to molds can cause symptoms such as nasal stuffiness, eye irritation, wheezing, or skin irritation. Some people, such as those with serious allergies to molds, may have more severe reactions.” In order to help prevent such health problems it’s best to know about the enemy…
According to the CDC, “molds grow best in warm, damp, and humid conditions, and spread and reproduce by making spores. Mold spores can survive harsh environmental conditions, such as dry conditions, that do not support normal mold growth.” Guess what kind of conditions typically exist in your home when the power goes out, especially right now in the summer heat? Of course, your regional climate (arid or humid) as well as the time of the year will make a huge difference in the potential for mold growth, including how fast it takes hold and spreads.
When I think of mold normally I picture it on my food… moldy bread, in particular. But, an equally significant danger that exists, at least with respect to a long term power outage, is mold growth on non-food surfaces, such as the shower (even in normal conditions), in your walls (such as with a lack of vapor barriers), and carpets (from inadequate whole-house moisture control). Basically, any location that can attract and hold moisture is a problem area. In a well-constructed, air-conditioned home, non-food surfaces are typically not a concern because moisture levels are kept at acceptably low levels (usually less than 50% humidity).
What Affects Mold Growth?
When the power goes out the ability to control the humidity in your home vanishes and… voila, mold grow. The question, therefore, is what to do to minimize mold growth when the power goes out?
In a nutshell, it’s all about temperature and moisture control, with moisture being much more important as mold cannot grow without moisture. Sadly, these are precisely the most difficult variables to deal with without central A/C. Having said that, you do have a few weapons at your disposal.
The first potential weapon is the power of the sun. Sunlight kills mold. So, it would be a good idea to open window blinds and shades in order to let in as much sunlight as possible. The major problem with this solution is that it also allows in heat energy, raising your home’s temperature, thereby promoting mold growth. The other major problem is that the locations where mold will likely be growing is precisely where sunlight does not reach. As such, this probably isn’t a viable solution.
So, what can you really do? Remember that the primary criteria mold need for growth is moisture. In the home that equals humidity. In order to lower the humidity level in the home you need to use wind power, that is, a draft. Not just any draft but a good cross-draft is in order. Not sure how to do that? Whenever you’re outside your home, pay attention to how the wind blows in your yard. Does it blow west to east, southwest to northeast, or what? And, more importantly, how does that relate to your home? Which windows and doors would need to be opened in order to best take advantage of that wind? Give it try some day.
The other major criteria mold need for optimal growth is higher temperatures (about 77 to 86 degrees Fahrenheit). Thus, you’ll want to keep below that target temperature range, if possible. On the other hand, apparently molds do not thrive in temperatures above 100 degrees Fahrenheit, which may be easily reached in many areas during summer months without central A/C. Unfortunately, you won’t thrive in such temperatures, so you’ll want to do your best to keep them down regardless of mold.
Without active cooling, the easiest way to lower temperatures is to reduce and reflect sunlight exposure (via passive cooling techniques) in conjunction with a strong cross-draft.
What Else Can Be Done to Minimize Mold Growth?
- You can combat mold growth on hard surfaces with a soap and water solution (and a scrub brush). An appropriate bleach solution (usually one cup of bleach to one gallon of water) or other disinfectant can help but won’t remove dead mold spores. Any wet boxes, clothing, or “soft” materials should be taken outside and thoroughly dried by the sun.
- You actions are also important. For example, do not boil water or cook inside as this WILL increase humidity levels inside the home. You might even want to take any water-related activities outside, such as bathing and washing clothes or dishes.
- Small shifts in your furniture placement may help too. In particular, move furniture away from exterior walls in order to allow for more air flow around the wall.
- You could also take drastic actions (for SHTF scenarios only) such as completely gutting your home of any carpet and the accompanying padding, especially carpet laid directly atop concrete since the concrete will wick moisture from the ground.
- Another option is to purchase a descent generator and large window A/C unit (or two) to aid with cooling problem rooms during the worst of the heat. This act may be far more welcome by occupants who are not at all concerned about mold… just the heat.
- Additionally, there are pre-disaster actions that can be taken to improve your home’s ability to combat mold such as installing appropriate vapor barriers in exterior walls, replacing carpeted areas with tile or hardwood floors, as well as ensuring any water leaks are or other moisture-related problems are remedied. Of course, these are costly and generally not something to contemplate unless you’re already experiencing mold problems.