A moss-free roof looks great and drains rainwater efficiently
We know that our home’s roof must be structurally sound to keep rainwater out of the home and to protect the family. The roof doesn’t have to all be about function, though—your roof can look great while protecting you. Moss growing on roof shingles is an annoyance that can detract from the overall aesthetics of your home, and it can even block the roof’s drainage system. If you’re comfortable climbing on your roof, you can learn how to remove moss from your roof in a few hours and have it looking and performing like new.
Follow these steps for a fresh roof in no time.
Cleaning moss growing on roof shingles is going to be a messy job. Water will splatter, and the green moss may end up on your clothes, possibly causing staining. Wear old clothing or a painter’s coverall.
Before starting, It’s important to understand that climbing onto your roof is dangerous; there’s the possibility of a slip and fall from this height, so this is not a job for everyone.
To clean the moss properly, you must climb onto the roof, so find some slip-resistant shoes. You’ll also want rubber gloves and a good pair of eye goggles. A harness is important safety gear as long as you know how to use it properly. If you’re uncomfortable working at tall heights, hire a pro to get this job done safely.
Place your ladder against the side of the house in a spot near the moss and where you can climb onto the roof easily. Once you’re on the roof, secure your safety harness, and you’re set to start removing the moss from the roof.
Using a garden hose with a low- to medium-pressure stream, start spraying the moss at the top-most peak in the roof. Continually work the spray at a downward angle to loosen and blast off the moss. Don’t use a pressure washing machine with shingles, as the powerful stream could damage your roof.
Next, use a long-handle, soft-bristle scrub brush to carefully scrape the remaining wet moss downwards toward the edge of your roof and the gutters. Be sure to brush gently and in a downward motion to protect your shingles from lifting upward.
Rinse the surface of your roof again using your hose on low-to-medium pressure. You may need to use your brush occasionally to help remove stubborn moss patches. Give it a final once over with the hose, and you’re all set.
Unfortunately, simply rinsing the moss away doesn’t guarantee the moss won’t grow back quickly. You can add a moss-killing product a couple of days after removing it to prevent it from growing back on the roof.
To apply the product, the roof should be completely dry with no rain in the forecast for several hours. Use a pump sprayer with a small jug that you can carry safely onto the roof.
You can buy a cleaning product from a home improvement store or online retailer. You also can make the cleanser yourself out of dish soap and warm water. You could use 1/2 cup of oxygen bleach mixed with 4 gallons of warm water.
After spraying, leave the product on the roof without rinsing it. This product should help you prevent moss from growing on a roof again for several weeks.
You have several options for moss disposal, depending on how decayed it is. For moss without too much decay, you can repurpose it, such as adding it to your flower pots or hanging baskets. You can try drying it out and using it for decoration around your home or selling it to local artisans who can find a use for it.
If you don’t need it directly for your garden or decorating, you can add it to the compost and mix it in with other composting materials. Keep in mind, this may cause a regrowth, so the best approach may be to put moss in a separate compost bin if possible.
Lastly, if it’s already decayed, you can simply throw it away in your household trash. If it’s a substantial amount of moss, consider a dumpster rental, especially if you have other projects going on, or hire a junk removal service to do the hauling for you. It’s a quick way to dispose of yard waste, including moss, all at once.
Deciding whether to do this job yourself or to hire a professional primarily boils down to whether you are comfortable climbing onto the roof and standing on it for at least a few hours. If you have a fear of heights or aren’t sure you can balance yourself on the angled surface of the roof, hiring a pro is almost certainly the better option.
However, if you are comfortable climbing a ladder to clean your gutters or standing on the roof to fix loose shingles, learning how to remove moss from your roof is a DIY job you probably can handle.
Figuring out how to prevent moss from growing on a roof can be a DIY job with a reasonable cost, especially if you already own some pricier items like a ladder, garden hose, and pump sprayer. If you need to purchase all these items new, expect to spend $200 to $250. If you already have many of these items, you will most likely spend less than $100 on this job.
The roof cleaning cost for hiring a professional company ranges from $300 to $625. However, your exact price will depend on your location, the size of your roof, the density of the moss growth, and the angle of the roof. Request a formal quote from a local roof cleaning company for an accurate estimate.
Scott Dylan Westerlund and Sara Coleman contributed to this piece.
Yes, moss can be dangerous for your roof if left in place to grow without treatment. The moss soaks up and holds moisture. Having a constantly damp roof could lead to problems with rot for the parts of the roof that consist of wood. Additionally, a patch of thick moss may draw insects and birds, which could damage the roof. Thick moss could block the roof’s drainage system. Water then may back up after a rainstorm and cause further damage that could eventually lead to roof repair expenses or the cost of roof replacement.
You could void your roof warranty using a power washer if you have a newer roof. With an older roof, you could knock loose older shingles. On the other hand, some people safely use a pressure washer to remove moss from a metal roof. Although you may want to use a pressure washer, the truth is that you probably don’t need it to knock moss loose. A garden hose and brush will do the job just fine and in a safer manner than a pressure washer.
You may become so frustrated with the look of moss on your roof that you contemplate whether to clean or replace your roof. Fortunately, you don’t have to go as far as replacing it. After cleaning the moss, you can use a chemical solution to keep it away. For further protection, trim branches that overhang the roof, as fallen seed pods and leaves on the roof allow moisture to collect, encouraging moss growth. Consider adding zinc-coated flashing to the roof, too. As rain washes across the zinc, it leaves zinc particles behind that inhibit moss growth.
