My Blog

Roof Cleaning: How to Kill Moss & Algae and Ways to Prevent Them

No comments
Your rooftop significantly influences the value of your home. Despite your best attempts to keep it in pristine condition, you may not have been successful in preventing algae or mold from growing on the shingles. You can maintain your roof’s integrity, appearance, and value by knowing how to eliminate and prevent moss on roofs.

Gather the Necessary Cleaning Supplies

Before you can tackle the job of removing algae on roofs, you first need to gather the necessary cleaning supplies. You may be tempted to use a power sprayer to clean the growth off of your roof. However, it is not recommended that you use this type of sprayer.

A power sprayer could damage the shingles on your roof if not executed by a professional. Further, using this tool could void the warranty on your shingles because the manufacturer will not cover any damages that result from excess force used improperly.

Instead, you are encouraged to use your garden hose as well as a spray nozzle that you can attach to it. The garden hose and nozzle will emit the right amount of force and power to remove the algae and mold from shingles. They also will not damage the shingles when cleaning algae from roofs.

Other supplies you should have on hand during the job include:

  • Pump sprayer
  • Safety goggles or glasses
  • Rubber gloves
  • Safety rope
  • Slip-resistant shoes
  • Ladder

You should also wear old clothing since you will be exposed to chemicals that could result in stains or bleaching. After you assemble the required cleaning supplies for the job, you can then turn your attention to what kind of chemicals to use to remove algae or mold from your roof.

50/50 Bleach and Water Mix

If you want to remove moss on roofs as inexpensively as possible, you could use a mixture of bleach and water. You should mix the bleach and water in a 50/50 ratio. Equal parts of both is sufficient for loosening and removing algae and mold that have grown on your shingles.

Once you mix the bleach and water together, you should use the pump sprayer to spray and cover the rooftop with the mixture. You should start spraying at the top of the roof and then work your way down toward the gutters. As the mixture runs from the top toward the gutters, it will coat and loosen the algae and mold on your roof.

After you coat the roof with the bleach and water, you can then use your garden hose and spray nozzle to remove the mixture. As you spray, the mold and algae should loosen and fall off the roof. You should continue to spray until the shingles are clean.

You should note, however, that you should spray down any foundation plants under the roof with water before you start the cleaning process. Bleach can be extremely harmful to sensitive plants. Spraying them with water prior to coating your roof with bleach and water will help protect them. You should also spray them with clear water after the cleaning job is done.

Commercial Cleaners

You also have the option of using a commercial cleaner to remove mold and algae on roofs. Most of the commercial cleaners available to homeowners like yourself are sold at big box or hardware stores. They contain ingredients like oxygen bleach, trisodium phosphate or TSP, and water.

Commercial cleaners are not dangerous to the environment and pose less of a risk to your lawn and foundation plants than bleach that contains chloride. Still, it is advised that you spray down plants and grass under the roof with clear water prior to using your preferred commercial cleaner.

You should also only use the product for cleaning algae from roofs on an overcast day. If you attempt to use it when it is sunny and clear, the sun will evaporate the cleaner before it can remove algae and moss. You will be left with growths on your shingles rather than a roof that is clean and free from these fungi.

Preventing Mold and Algae Growth on Your Roof

You can spare yourself the trouble of having to clean your roof of mold and algae by taking some simple preventative measures. Preventing the growth of fungi can be as simple as installing zinc or copper flashing on your roof.

To install this flashing, you should purchase two to four-inch strips of copper or zinc from your local home improvement or hardware store. You should then install the strips of flashing under the row of shingles closest to the peak of the roof.

You would do well to leave an inch or two of the metal exposed to the elements, however, when it rains, some of the molecules in the metal will wash down the roof and kill algae and mold before they can take root in the shingles.

Installing this flashing is not difficult and does not take a lot of time or muscle. You can use roofing nails or screws with rubber washers to hold the metal in place.

You can also loosen self-sealing tabs on the top row of the shingles with a putty knife and then slip some of the sheet metal under them. You can then use roofing nails to secure the metal in place.

You should note that the flashing itself can be prone to moss buildup. You can keep it free from moss, algae, and mold by cleaning the strips first with a brush and then using a commercial cleaner or a 50/50 mix of bleach and water to remove the debris.

Algae and mold tend to grow on shingles that are not properly cared for or cleaned. Once this fungi takes root, they can quickly damage the value, appearance, and integrity of the roof. You can remove such growth by using a mixture of bleach and water or a commercial cleaner and then installing flashing on your roof to prevent new growth. Contact us today if you’re having trouble with removing moss and algae.

Roof Cleaning: How to Kill Moss & Algae and Ways to Prevent Them

Leave a Reply

Your email address will not be published. Required fields are marked *