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Why Does Moss Grow on the Northside of the home first?

Many types of growth attached to home siding and roofs. If you walk around your home, it’s safe to bet that one side is dirtier than the others? But what causes this? It’s a combination of many variables, but one primary factor stands out.

3 Key Components

If you happen to have a compass or open a compass app, you’ll typically find that the side of the home that’s most dirty is typically facing North. You see, growth on homes needs three critical components; water, food, and a moderate temperature. The north side of the home typically gets the least amount of sunlight but just enough to make for the perfect habitat for moss and algae. The rest of the house gets too hot for growth to flourish unless you look in the shaded, damp areas like along downspout lines or in the shadows of dormers. The growth is continuously fed with mineral deposits from the wind and rainfall. With all 3 components in line, the north side of your home should develop much faster than the rest of the home.

How Can I Prevent It?

There is not much you can do about the sun so let's look at the other key components. Many homeowners will apply Moss Out or Moss Be Gone. These powders are applied to the peaks and valleys of the roof and contain primarily Zinc. The zinc metal changes the power of hydrogen (PH) balance of the rainwater that hits the roof. This makes a less than ideal habitat for growth to occur but does little in the way of killing off growth that has already taken root.

Why Should I Clean It?

Besides the apparent cosmetic benefits of cleaning your home exterior, growth that appears on the outside of the home will work its way into the home, bringing moisture and rot with it. Neglecting the outside of your home can cause structural damage or risk the health of those living inside.

How Should It Be Cleaned?

If unchecked, the growth can spread to the entire roof creating blankets of green fuzzy carpet. If you are clearly able to see moss or algae growing from the ground, call a professional to perform a softwash. See our article: When Is It Time To Clean My Roof?

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