Roof Moss Removal Keeps Your Shingles in Shape

People living all over the U.S. with all kinds of roofs can have problems with moss and algae accumulation. Because moss and algae need water to grow and spread, regions with more rainfall and long periods of high humidity levels are more susceptible to mold and algae problems. Roof moss removal will keep your roof clean and mold-free.

Usually, you’ll see more moss and algae growth on north-facing portions of the roof, as they tend to dry out more slowly. Also, a roof that’s shaded by a large tree is more susceptible to moss growth.

A mossy roof might resemble a fairytale cottage, but moss and algae can cause serious damage to your roof. If your roof is made of untreated wood and/or asphalt, thick moss keeps the materials damp for sustained periods of time. Sustained exposure to moisture promotes wood rot and will erode asphalt.

Luckily, roof moss removal is pretty simple, and it will definitely extend your roof’s lifespan. Here’s how to do it: use a standard bristle scrub brush with a pole attachment. Push the brush down the roof to disconnect the shallow root system of the moss from the shingles. Avoid brushing up the roof, as you risk breaking the bond between the shingle layers.

You’ll see that most of the moss starts growing at the top of the vertical slots between shingles—this is the last place that water evaporates from the roof. Once you’re done with your roof moss removal, check to make sure that the colored ceramic granules between the shingles are still in place. If they’re gone, you’ll see the interior fiberglass mat of the shingle—which means your roof will be in need of replacement in the near future.

Green and black algae, on the other hand, won’t harm the actual roofing materials because they don’t develop roots. Unlike moss, though, algae present a clear aesthetic problem. Although you’ll need to use a different method than that of roof moss removal, you can remove both black and green algae.

Instead of heavily abrasive chlorine bleach, try non-toxic oxygen bleach as a roof cleaner. Mix the powder with water and apply it to the roof when it’s cool—an overcast day is best. Keeping the surface wet with the solution for just twenty minute usually does the trick, although you might need to repeat the process several times if your roof is severely stained.

To keep moss and algae at bay, you can introduce copper onto the roof surface. You can find plenty of roofing supply companies that sell tin, copper, and galvanized metal products to residential roofers, and they can sell you rolls of copper.

Cut strips about 5 or 6 inches wide and about 10 feet long. Use a metal brake tool to put a 20-degree bend about a half inch from the edge on the length of the copper strip. Put these copper strips near the top of the roof by sliding the unbent edge up under a row of shingles. The bent edge and about 4 inches of copper should be exposed. When it rains, the copper strip will act like a sort of gutter and the water will carry copper molecules down onto the roof. Both moss and algae dislike copper, so further roof moss removal should be unnecessary after this procedure. The copper will eventually turn dark brown, then to its distinctive green color.