Simple Guide to Cleaning Moss from Asphalt Simple Guide to Cleaning Moss from Asphalt

An asphalt roof may be very durable but it won't completely remove the hassle of cleaning moss off the surface of your roof. Asphalt is susceptible to damage from moss and so the growth must be removed carefully to prevent any problems.

With all of the right tools and materials available you shouldn't have any problem cleaning the moss off your asphalt roof with ease.

Why is Moss a Problem

Moss is a green plant which grows on rocks and all sorts of other materials including roofs. The moss doesn't only look unattractive, but it also can cause a problem with damp. Moss is like a large sponge which means it will absorb water which can affect the efficiency of your roof.

Protecting Plants

Your roof will be designed to allow water to run off, you will need to protect any of the plants below the roof so that they won't be damaged by the water and cleaning agents running off the roof while you remove the moss. This can be done by using upturned plant pots or plastic sheeting supported by canes.

It's also important to protect your eyes by wearing safety glasses of goggles. A ladder will be required to reach your roof, so make sure that you are careful and fully prepared.

Getting Rid of Moss

Use a hose to wet the affected area of your roof. Once the roof is sufficiently wet you should then sprinkle on laundry powder all over the affected area. This will help to loosen the moss and also get rid of any stains which can look unsightly. Allow the powder to stay on the roof for a couple of minutes.

Wear some gloves and use a brush to scrub the whole roof. It will work best if you scrub the roof in one direction as this will create more soap suds. The suds should deter the chances of moss growing again.


When the area has been scrubbed and cleaned it's then time to use your hose again to rinse off the entire area. If there are any patches of moss which remain then the process can simply be repeated as many times as required. You might have to do this several times before you can get rid of the whole problem.

Once you've finished washing the roof you can remove the plastic sheeting and protection for the plants.

Don't Use Pressure Washers

It can be tempting to use a pressure washer on your roof. Although this will get rid of all the moss very quickly, there's also a very good chance that it will crack and damage your roof. Pressure washers are not suitable for this type of project because they are too powerful. Even getting them up to the roof will be difficult.

It might be slower to use a brush and soap, but this is not only a safer option, it's also much more efficient. Take your time and don't get disheartened when you have to repeat the process several times to get rid of all of the moss.

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