The Modern Home?

These days there is more free information available online to the consumer, empowering us to be smarter with our time, money, and in this case our health. We have already established the fact that mold spores are present just about everywhere and that they can grow if we create environments where mold can thrive. Here is the key to living in a world where mold can show up just about anywhere - prevention is the best solution to control all mold problems.

IMPORTANT!

Mold needs 4 things to grow.

1. Spores (seeds of mold)

2. Food (organic material)

3. Water or high humidity

4. Temperature between 32 degrees and 100 degrees F. (0 and 43 celsius)

We can’t eliminate the organic material – our homes are made of it. We can’t get out of the temperature zone – we like that zone ourselves! And we can’t get away from the spores – they are everywhere (you’re breathing some right now!) What we can control is the moisture – and therein lies our secret to mold prevention.

To Your Health:

You can’t find a doctor who says mold in a home is good. You can’t find a doctor who says mold in your home is “not bad.” It’s bad. It’s all bad. Besides irritating people with asthma and mold allergies, studies show that prolonged exposure to mold can actually cause asthma.

Q: 

Do we have more mold today than we did a hundred years ago? Or do we just have higher standards and are more sensitive to mold?

A. 

The answer is both.

Let’s Talk About Some Rules of Building Science –

1. Moisture goes from more to less, and hot to cold.

2. Wood and organic materials are “hygroscopic” – meaning that when the air around them is damp, the materials absorb moisture out of the air and come into equilibrium with the moisture content in the air. When the air dries out, the materials dry out. That’s easy to understand. Wet air, wet materials. Dry air, dry materials. It’s okay for organic materials to get damp, so long as they can dry in a day or two before mold grows.

3. When you cool the air, you raise the Relative Humidity unless you take water out of it. In fact, for every one degree you cool it, you raise the Relative Humidity by approximately 2.2%.

Air Leaking OUT  causes air to leak in.

In homes built a hundred years ago, we had very leaky wall, ceiling and floor assemblies with no insulation. We had heat flow through the building envelope – inside to outside in the winter, and outside to inside

in the summer. The house dried to the outside in the winter, as there were no vapor barriers, air barriers, or insulation preventing moisture from leaving the building. This was a good thing relative to preventing mold. Of course we were shivering in our homes and it took a great deal of energy to heat our homes (unevenly), but at least they could dry out.

Today;s home

Today we have homes that are much tighter. Are they “too tight”? Not hardly. In fact the average home has a long way to go before it’s too tight. But we have to pay attention to how we build homes – where we put vapor barriers (they need to be on the warm side), what kind and how much insulation we install, and vent excess moisture outside (bath fans, clothes dryers, kitchen exhausts etc.)

We need to control our basements and crawl spaces from leaking obviously, and not allow air from the earth into our homes. We should not allow outside air into a below-ground space such as a crawl space or basement, because we will pay an energy penalty in the winter, and have high relative humidity and condensation in the summer time, causing mold.

One thing the modern home has today is air conditioning. This makes preventing mold more difficult? Why? A hundred years ago the way you (tried to) cool down was opening windows and maybe running a fan. We were not changing the temperature of the outside air as it came into the house, and therefore were not raising the relative humidity by “squeezing” the air to a cooler temperature. Today, when summer air leaks in, we cool it because the home is air conditioned. Air conditioning removes relative humidity, but not perfectly in all areas of the house. In fact, it creates cool surfaces such as ducts and wall surfaces, where the relative humidity is high and even up to 100% (condensation). All mold needs is relative humidity over 70% (The higher it is, the more different species of mold like it).

Another thing that is different these days is we are building homes from fast-growing farmed trees as opposed to old-growth trees. When you cut an old log you’ll notice the darker inner core of the log, perhaps 3⁄4 of the wood. This is “heartwood”. The outer rings are lighter and called “sapwood”. Sapwood has the sugary cellulose that mold loves to grow on – more so than heartwood. With today’s fast-growing farmed trees, the trees may only be 30 years old when they harvest them and they are nearly all sapwood.

We also have lots of plumbing these days. More fixtures that use water means more chances for leaks. The water line to the ice maker on the refrigerator, dishwashers and the multiple bathrooms we have in modern homes are all more opportunities for leaks. All the other ingredients for mold are present.

The insurance industry top water damage claims are not from hurricanes, and floods, but leaks from pipes, water heaters, and washing machine hoses malfunctioning in the home.

Are we more sensitive to mold these days? Certainly our standards for health have gone up. We also spend a lot of time indoors compared to 100 years ago. By not being exposed to outdoor mold spores as much, we may not have built up a resistance or immunity to mold spores and pollen. There was no Claritin in 1900!

Today’s drug industry is a thriving business. The doctor’s never ask you, “What’s going in the home?”

Can you clean mold with bleach?  The problem with bleach:

A lot of people think that mold is no big deal, they have seen it all their lives in bathrooms or basements, they just use bleach to clean it up and forget about it. Did you ever wonder why it keeps coming back in the places where it was removed? Now at least you know that if the area is wet or damp in those places it will encourage mold to return, but did you know that bleach actually feeds the mold you thought you were cleaning? In high school you may have taken a chemistry class, and on the molecular level they would have discussed compounds like nitrates. Tiny little traces of these compounds are left behind when Sodium Hypochlorite (Bleach) is applied to a surface. These compounds are fertilizer for the next group of molds to land there!

The water in the hypochlorite penetrates below the surface of porous materials like wood framing, while the bleach is left on the surface and eventually gases off into the atmosphere. The root of the mold fungus is left below the surface and regenerates again over time.

The Risks of Cleaning it Yourself ? 

The problem with do-it-yourself...

Do-it-yourself projects are popular, with national big box stores offering the materials and advice for home repair and improvement. There are certainly many books available by experts to walk a homeowner through small-one-hour projects to ambitious multi-person remodels. There are of course a wide variety of professional service companies also marketing their talents for hire. Indeed, some work should be left to professionals, such as when permits must be pulled for electrical work.

Mold removal, testing, and prevention should all be left to professionals licensed in this work, equipped to protect themselves and homeowners from the potential hazards mold can present.

Professionals should be licensed in the particular service they are offering to you, and your home. A written contract should always spell out what services or products you are purchasing, any warranties they are offering, and what standards determine the success of a project.