Despite its obvious importance, the roof tends to be an area of the home that goes overlooked and ignored. That is, until it becomes so excessively dirty and disheveled that ignoring it is no longer a possibility. Or worse still, your once-pristine roof is now home to a thriving buildup of moss, which over time can eat away at your shingles. The shingles that we are talking about here are commonly known as asphalt shingles or composition roofing.

If you have moss, ignorance isn’t an option–you need to get it taken care of ASAP. On the plus side, shingle moss cleaning is the kind of job that’s perfectly possible to tackle manually. That is, just as long as you know exactly what the job entails before going ahead, in order to avoid doing more harm than good.

Here are the top 7 most common mistakes to avoid while cleaning shingle moss:

1) Dying or getting hurt.

Not a joke. People die every year climbing on their roofs or falling off ladders. So do children, grandchildren, neighborhood kids, and anyone else that gets on your roof without proper safety equipment, including proper ladders, and personal protective gear. And here is the thing, if you get killed or hurt, it’s someone else’s problem. But if someone you asked to get up on your roof gets hurt or killed, it’s your problem. Because you become their employer in the moment that you make the request. So you are liable for any injuries or deaths that occur. That’s why professional companies insist on safety compliance and carry Workers Comp insurance. To protect themselves, their workers, and you.

2) Pressure Washing

The biggest and most common mistake of all, is shingle moss cleaning by way of pressure washing. While this method can technically get the job done, it will cause more damage than good if not done carefully. While removing the moss, you may end up inadvertently causing serious damage to your shingles or blast them clean off your roof. It’s perfectly fine to use a pressure washer on a low pressure setting to rinse a roof when the moss and debris has been loosened and/or removed. Here is our advice: unless you know (as opposed to think you know) exactly what you are doing, don’t use a pressure washer on your roof. And don’t let a non-specialist contractor do it, either. This is a very specific area of the industry, and one mistake can be catastrophic for your roof–and your budget. For some types of roofs this may be okay, but NOT for shingled roofs.

3) Harmful Chemicals

The same also goes for chemicals. You, as the homeowner, can put whatever you want on your roof. However, if you ask someone else (again, child, grandchild, neighborhood kid, some guy off the street), you must comply with the law. The law says anyone except you must have a Pesticide Applicator License, and may only use EPA approved product, and comply with the label instructions. It doesn’t matter if it claims to be “organic” or “environmentally friendly,” if someone puts it on for you, they must be licensed and must use a legal product. Even the properly licensed products, used improperly, can cause serious illness or injury. This is not one of those areas where if a little is good, a lot must be better. While there are many possible powerful chemicals that can get the job done, they may do so at the expense of your shingles’ health. Not to mention, your own. Chemicals will kill moss on contact and make it easy to remove even the heaviest buildup. However, they can compromise the integrity of your shingles by accelerating corrosion, rot, and decay. In addition, potentially harmful runoff can find its way into your home and your garden, posing a direct threat to the health and safety of people and pets alike. Our advice: hire a properly licensed professional to apply EPA approved products in the proper way. This protects you, your roof, and the environment.

4) Abrasive Scrubbing

A little elbow-grease might be called for, but it’s important to avoid getting too carried away. To scrub roof shingles too aggressively is to run the risk of damaging the surface, compromising the protection they provide and ultimately accelerating their deterioration. Not only this, but an overly-intensive scrubbing action can also dislodge roof shingles, causing them to come loose or perhaps fall from their position entirely. If you’ve decided to take the hands-on approach to roof shingle moss removal, be sure to use a medium-firm brush and a relatively gentle scrubbing action to minimize damage. If the moss doesn’t come loose easily enough, it clearly needs further treatment before going back to the brush. If you plan to do this yourself, please see item 1), above.

5) Not Considering Roof Type

There’s no such thing as a one-size-fits-all roof cleaning product or approach. With so many different types of roofs and a variety of common cleaning duties to carry out, there’s a near-endless range of products on the market for a reason. Choose the wrong product and while you might get rid of the moss, you could also cause serious damage to your roof. From wood to slate to concrete to metal, there are many purpose-made products available for every type of roof across the board. It’s the same story for the job itself too–some products are made for moss removal, others algae, some general grime build-up and so on. If in any doubt, note the type of roof you have and the job you’re looking to tackle, before seeking advice from an expert.

6) Overlooking Prevention

One of the biggest mistakes any homeowner can make when looking to tackle a moss problem is not realizing that there really is no permanent solution. There’s really no point investing your time, effort, and money in a shingle moss clearance effort, only to then sit back and allow it to return with a vengeance. At minimum, you should treat your composition roof every three years. Regular treatment will prevent build-up and prevent the necessity for removal. Any mechanical removal, that is brushing or scraping, of moss is going to cause abrasion to your roof. Getting ahead and staying ahead of the moss will provide the longest roof life. Make sure your roof gets the maximum amount of light and air. Trim branches and trees away from your house and roof. At least 4 feet from your roof will help a lot. If your roof is heavily shaded, you may need to treat annually or every other year.

7) Not Calling the Licensed Professionals

Last but not least, dealing with roof moss cleaning and treating without calling the professionals could prove to be a mistake. Unless you are prepared to be sure that you are OSHA safety compliant, are prepared to be ODA (Oregon Department of Agriculture) compliant in terms of the products you use and their proper applications, and have significant experience working on roofs as a professional, have the pros do the job on your behalf. It will save your life and limb. And the environment.

For a free estimate to have our expert crews take care of your roof, click the button or give us a call at (503) 407-3346.

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