Moss is more than an unsightly nuisance. It develops on your garden furniture, lawn, concrete, or even your roof and can cause harm over time as it absorbs water and keeps the roof moist. It can also collect water that is draining down your roof tiles on a slanted roof and causes the edges of asphalt shingles to rise, making them more vulnerable to blowing off in severe winds.
So, if you spot some green bunches blooming in shaded areas all over your roof, that is when you know you have a moss problem, and it is time to treat it right away. Continue reading to find out how to remove moss from the roof naturally!
Table of Contents
What is moss?
Moss is a plant that collects water via its leaves, and therefore it does not need soil to thrive because it does not get the nutrients through its roots. It can grow in any location with appropriate moisture levels. Moisture collects in areas with low sunlight, and because moss doesn’t need the sun to thrive, it can grow in any gloomy environment.
What causes moss growth?
Moss and other plant or fungal development is a regular concern for homeowners, even in parts of the country where there isn’t much rain. Moss, lichen, and algae thrive best in moist, shaded environments. This usually happens with a north-facing roof that doesn’t get much sun. Wind, birds, and bugs can transport spores, and when the conditions are right, they will bloom.
While newer asphalt, fibreglass, or slate roofs may have a moss-resistant chemical coating, the growth of moss can be a widespread problem on older roofs. Even if you clean your roof shingles on a regular basis, you can still spot moss in the cracks between them. When moss grows on a metal roof, the protective coating on the metal tiles is likely to have worn away. That is because moss can hold water and stay wet, leading to rust and corrosion.
Repainting your roof is the greatest option for eradicating huge spots of moss from a metal roof. A professional roofer has the knowledge and skills to properly clean moss and refinish your roof, as well as recognise signs of wood rot or leaks beneath your roof.
Moss and lichen have evolved to last for months without water, and they will attract a wide variety of insects and birds as they get more established. Other plants may begin to grow in the mossy areas if left untreated, resulting in greater moisture build-up that can cause significant structural problems for your entire roof.
Why is moss bad for your roof?
Moss and algae can harm your roof both directly and indirectly. Allowing big patches of moss to grow on your roof causes your roofing materials to decay over time. Furthermore, the water retained by the moss accumulates in gaps between your roof’s tiles, where it can tear the tiles apart when it freezes and thaws, inflicting even more harm. On the other hand, removing your moss can also be just as harmful and damaging.
Inspecting the roof before you start
Ideally, a professional roof check should be performed once or twice a year to keep an eye on potential damage before you end up with some costly repairs. If you have a large patch of moss on your roof, it may have already caused damage, anyways.
It may be more cost-effective to replace your roof rather than spend time removing moss in some cases. Check for any signs of leaks and add a sealant when possible. Also, look for evidence of rotting timber in the attic. You might be able to replace it without completely tearing it out, depending on the extent of the damage.
A skilled roofer can inspect for leaks, replace or repair roofs, and reseal or replace any damaged flashing. They can also detect structural issues quickly and have all the necessary gear and expertise to work safely on your roof.
If the roof inspection reveals that the structure is too vulnerable, then you better replace your roof. You can then follow preventative tips on your new roof to keep the moss from returning, which we’ll go into at the end of this article.
Natural ways to remove moss from your roof
If you decide to remove roof moss on your own, you must take all necessary safety steps. Make sure you’re using a rubber-footed safety ladder and that you have someone to spot you. Always wear a helmet and rubber gloves and never walk on your house’s roof.
For traction, roofers use a safety belt and rubber-soled boots. If necessary, they may also add toe boards and roof brackets. If you can’t fix the problem from a ladder, you risk a serious injury, so be extra cautious.
If you can reach the growth of moss from a ladder, you can try these methods below, but be careful not to harm your roof in the process:
1. Use a gentle scrub brush to clean the roof
Scrubbing the roof is a delicate job, and you could end up damaging it. Asphalt shingles have protective oils and tar on them to protect them from UV light and moisture, but if you use too much pressure, the shingle granules might be pushed off.
A protective coating is applied to most metal roofs to prevent corrosion. You can shorten your roof lifespan if you use a stiff brush or scrub too aggressively. Instead, use a soft-bristle scrub brush and work gently when cleaning your roof to avoid scratching the roofing material. Start at the top of the roof and work your way to the bottom.
Scrubbing the moss can help spread the spores, and in as short as six weeks, you may end up with even more moss growth. Furthermore, moss fragments that break off can regenerate. Even the tiniest amount of remaining moss that a brush misses can swiftly restore itself, so make sure to cover everything and use as low pressure as possible.
2. Wash your roof
It’s a good idea to clear the entire roof of any debris that could shield the moss spores before using any agents to eliminate any leftover moss. At first, it may seem that pressure washing your roof is a straightforward answer to roof cleaning, but it is not.
Pressure washers can cause leaks by damaging protective coatings. It’s far better to use a regular spray attachment for a garden hose while rinsing out your roof, but be mindful of any water that seeps down onto your ladder, as this might considerably increase your danger of slipping.
3. Kill the spores
You can kill moss development on your roof surfaces with various sprays. White vinegar or a 50/50 chlorine bleach (or oxygen bleach) and water mix in a spray bottle are popular and effective moss killers. Regrettably, they are also capable of harming other plants.
Any of the sprays that drop on your landscaping after you rinse it off could cause a lot of damage. So, to protect your plants from runoff, properly moisten them before rinsing the roof. You can also cover any susceptible plants or walkways with plastic sheeting to reduce exposure.
Instead of washing the sprayers, some homeowners choose to leave them on the roof. Even though bleach and vinegar evaporate quickly, they can be harsh on your roof and destroy any protective coatings. In addition to vinegar and chlorine bleach, there are a variety of moss treatments available in the market.
Beneficial ingredients such as baking soda or zinc salts, which are less likely to hurt your lawn or contaminate water supplies, are among the most environmentally friendly options. These are still effective in killing the plants and fungus that have taken up residence on your roof while causing no damage to the roof structure.
4. Change pH levels
Lowering or raising the pH level is a limiting factor that restricts and kills moss habitat. Moss grows best at pH 8.0 to 8.5, but it does not thrive at pH 3.5.
How to prevent moss growth
Once you clean your roof from moss, you should then take some preventive measures to eliminate the chances of moss regrowing. Here are some tips you can follow:
- One of the most effective moss removal deterrents is sunlight. To avoid shade, keep trees pruned away from your roofing system. This will help keep your roof safe from fallen limbs and animals seeking refuge in your attic.
- Spores are attracted to leaves, sticks, and other organic materials. Moss spores might take root on your roof if you don’t clean your roof and gutters regularly.
- It’s also important to have good roof drainage to keep things dry and maintain good airflow, especially if you have a cedar roof or other wooden shingles. Wood rot, mildew, mould, and leaking roof can occur when standing water is on your roof.
- A protective zinc coating protects galvanised steel roofing panels from corrosion preventing plants and mould from growing on your roof because of the zinc. The covering might wear out over time or be harmed by falling debris.
- Install zinc strips along the ridges of your roof if you have a typical shingle roof. As it rains, tiny specks of zinc will run down, eliminating dead moss or algae growth before it becomes a huge problem.
With the methods listed above, you should now remove moss naturally. It’s a win-win situation – you get a moss-free roof while saving the environment! DIY roof maintenance is risky, and even a minor error can put your roof in jeopardy, so be sure to follow all the safety tips, and you are good to go!
Coming next: How to clean moss off roof tiles step-by-step.