1. It doesn’t look good. The blue-green algae (gloeocapsa magma) makes a mess of your roof with unsightly splotches and lumps. You spent a lot of money on your roof, so don’t let the green (gray) monster take over.
2. It blocks the sun. Too much moss doesn’t allow the roof to properly reflect the sun’s rays, therefore the cost to cool your house in the hot summer months, increases.
3. It blocks gutters and drainage. Moss is most problematic when it starts to block gutters, outlets and other drainage points.
4. It blocks water flow. When moss builds up, it impedes the natural action of water to run straight off the roof. It soaks up water, which then lies over the tiles for long periods of time. When wet, moss can weigh five times as much as when dry.
5. It holds in moisture, which can lead to rot, mold and mildew. Keep your roof dry, keep your house dry.
* Next up, we will tell you how to remove that intractable moss.