We all like to be green – but avoid the moss


If you thought that layer of green developing of your roof was a good thing – think again. Moss can root itself onto the top layer of the granules on roof tiles, cutting down on the protection that shingles provide. We’ve even seen moss grow into the wood under the shingles, requiring the entire roof to be replaced. There’s something to think about!

So how to keep your roof moss free?

In our experience, this is more tricky than you might think. There’s no permanent solution, unless you want to go with a metal roof! Big trees cast shade on a roof or deck, or drop needles and leaves, creating optimal conditions for moss spores. Even if you clean the moss off your roof, if your neighbor has them, the spores will just migrate back on to your roof.

So we recommend treating your roof, which will kill any existing moss and prevent re-growth for some time to come. If you’re serious about protecting your roof, then combine treatment with tree pruning and trimming branches which casts a shade on your roof. This will keep re-growth in check.

We never recommend pressure washing for roofs (unless they are tile) because it tears up shingles.

If you’re getting rid of moss to protect your investment in your roof, then use a licensed company. There will be cheaper alternatives, but you might end up saving a buck today, to lose thousands on potential roof damage in the next couple of years.

Action Northwest is a licensed Commercial Pesticide Applicator through the Oregon Department of Agriculture.