If you don’t know the answer to this question, you’re not alone. We get asked daily by homeowners and renters about things that are on their roof but shouldn’t be, including chunky green moss, lichen, black streaks, and their kids’ frisbee. And every day we help our clients solve these issues (including the frisbees!).
Getting moss off your roof can be done one of several ways, but they generally fall into one of two categories:
- Physical agitation. This is best for large, chunky moss and can be used on many types of roofs. Typically, this is done with bristle brushes, rakes or pressure washers, however, it must be done with care or the roof can easily be damaged. Abrasive techniques such as these are best reserved for “tougher” roof made of metal or concrete tile, however less aggressive brushing can be done on shingle and clay tile roofs as well.
- Chemical treatment. This is commonly used on black streaks and tough to remove lichen. It can also be used after physical removal of larger moss to eradicate any remaining moss roots or spores. Chemically treating a roof can be done with minimal pressure and reduce the risk of damaging the roof. Chemicals employed can include trisodium phosphate (TSP), sodium percarbonate, or sodium hypochlorite.
Now that we know the two primary ways to get moss of your roof, let’s talk about what NOT to do to get moss off your roof.
- Unless you are trained on roof and ladder safety, you should NOT get on your roof in the first place.
- You should never use aggressive agitation such as pressure washing or wire bristle brushes on asphalt shingle roofs. This will cause the granules to dislodge and will take years off the life of your roof.
- Some chemicals used in treating roofs are harmful to plants and animals, so you should NOT apply them without a trained professional on hand to assist in keeping the surrounding area clear and/or covering or heavily wetting nearby plants.
- If you see what looks like a putting green on your roof, you should NOT plan any golf outings or downtime with your family – you will be spending much of your weekend on the roof!
Of course, you could always just call the professionals at All-Clean! and let us handle the moss removal and you can keep your feet on the ground and spend more time with your family and friends!