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A whole lot of air----a whole lot of “hot-air”

Every year I get to watch one of my neighbors have their roof cleaned.  I have posted in the past about the damage that can be done to roofs from pressure washing and that post had a video of the effect of pressure washing on the shingles.

This year I could hear the pressure washer again so I ran to the window to check it out.

This year’s cleaning was different.

The roof cleaning service was utilizing a supposedly better method of cleaning the roof.  The process uses a stream of “air” instead of “water.”

As I watched the process it became clear that this method is absolutely no better than using water and might actually be worse.

As you watch the two videos, I will let you decide so that the next time you have your roof cleaned—you will pick a method different from either water pressure washing or air pressure cleaning.

As you can see in both videos, the shingles are no longer adhered and will be very vulnerable to wind damage in the future.  All that flapping up and down is a little like leaves blowing down the street.  In time it will be shingles blowing down the street.  Several years have been taken off this roof by both methods of pressure cleaning.

Of course the TV advertising says nothing about this—perhaps the cleaning companies work for the roofing company.

My new roof does not have this issue.

 

Charles Buell, Real Estate Inspections in Seattle.

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Seattle Home Inspector

 

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Comment balloon 23 commentsCharles Buell • December 18 2013 05:30AM

Comments

Oh wow.  The air one looks even worse.  It must take more pressure to make that happen with air.  What would you suggest homeowners do?  Is it better to do nothing? - Debbie

Posted by Women of Westchester Working Together, Women helping Women get ahead (Women of Westchester Working Together) over 4 years ago

There sure does look like both pressure cleanings take its toll on the roof Charles.

Posted by Tom Arstingstall, General Contractor, Dry Rot, Water Damage Sacramento, El Dorado County - (916) 765-5366, General Contractor, Dry Rot and Water Damage (Dry Rot and Water Damage www.tromlerconstruction.com Mobile - 916-765-5366) over 4 years ago

Hi Charles,

Why is there not any Zinc strips installed on those roofs that have mold amd moss issues?

The zinc strips are a good way to reduce this issue. Crazy way to ruin your home buy power washing in that manner.

Have a great day in Seattle. Happy Holidays.

Best, Clint McKie

Posted by Clint Mckie, Desert Sun Home, Comm. Inspection 1-575-706-5586 (Desert Sun Home, commercial Inspections) over 4 years ago

 Good morning, Charles. I wish that I could have a metal roof in my area.  The fire marshal outlaws them in residential neighborhoods.

Posted by TeamCHI - Complete Home Inspections, Inc., Home Inspectons - Nashville, TN area - 615.661.029 (Complete Home Inspections, Inc.) over 4 years ago

Debbie, I have gone around and around with the answer to your question and I am pretty sure there is no way to clean an asphalt roof that does not harm to roof to some degree.  I wish someone would do a study of the change in life expectancy over doing nothing.  Of course the really heavy laminate asphalt shingles might hold up a little better to pressure washing.  The real answer in my opinion is to get away from composition roofs all together.  Of course merely accepting a shorter life span is an option as well--including WAY shorter if the thing blows off.

Tom did you notice the little white seperation strips blowing out from under the tabs on the air video?  Some of the pieces of moss were blasted under the shingles and now the roof is not laying flat---again making the roof more vulnerable to wind damage.

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) over 4 years ago

Clint, because the sinc strips don't work very well.  You can even get shingles with zinc granules.  They both help a "little" but are not the whole answer.

Michael, that is interesting.  Around here, in fire prone areas the metal roofs are required.

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) over 4 years ago

Clint, here is a picture of an installation of zinc strips and moss.

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) over 4 years ago

Good morning Charles. I think that you have done a service to folks who never knew this. I have seen shingles flapping around after a cleaning, but thought if the direction was right, it would make a difference. Apparently not. Suggested.

Posted by Sheila Anderson, The Real Estate Whisperer Who Listens 732-715-1133 (Referral Group Incorporated) over 4 years ago

Sheila, I think this is a difficult problem with no easy answer--especially living in the "Moss State."

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) over 4 years ago

I have a neighbor that had copper roofing put up. I was amazed to see it due to the cost of copper. It is only a two bedroom home on stilts but still....

Aluminium roofs are pretty common down here and they last forever. While new ceramic tiles look great, once they get older they turn pretty ugly if not cleaned.

Posted by Barbara-Jo Roberts Berberi, MA, PSA, TRC - Greater Clearwater Florida Residential Real Estate Professional, Palm Harbor, Dunedin, Clearwater, Safety Harbor (Charles Rutenberg Realty) over 4 years ago

Barbara-Jo, there is nothing prettier than a copper roof.

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) over 4 years ago

WOw, that does more harm than good!  I like your metal roof!

Posted by Kristin Johnston - REALTOR®, Giving Back With Each Home Sold! (RE/MAX Realty Center ) over 4 years ago

Kristin, thanks.  I LOVE my metal roof.  While I would never "have" to clean it, I can pressure wash it if I want to.

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) over 4 years ago

OMG.... Made me want to come out there and shake the guy by his shoulders.... "Dammit man, can't you see what you're doing to this roof?"

I wonder what the over/under is on pounds of granules in the gutters?

Posted by Fred Hernden, CMI, Albuquerque area Master Inspector (Superior Home Inspections - Greater Albuquerque Area) over 4 years ago

Oh my goodness. I have never seen anything so stupid.

Posted by Juan Jimenez, The Richmond Home Inspector (A House on a Rock Home Inspections LLC) over 4 years ago

Fred, there is another cost of composition roofs that is typically not factored into the cost of such materials---plugging up perimeter drains

Juan, it seems to be right up there doesn't it?

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) over 4 years ago

I know a guy who's neighborhood HOA dinged everybody for roof algae.  Some had moss, like that house, though not at thick.

This guy took the bull by the horns and developed a pretty good formula for cleaning his roof, gently and completely.  It has lasted two years so far, without any further outbreak.  It works on everything growing on the roof, and merely hoses away.  His formula doesn't damage the grass when diluted by so much rinse water.

It cost him about $35 to do his roof.  Another neighbor had their roof cleaned for $650.  Their roof algae is already back!

Here is where you can see this genius formula he developed -

http://www.jaymarinspect.com/roof-black-algae.html

Posted by Jay Markanich, Home Inspector - servicing all Northern Virginia (Jay Markanich Real Estate Inspections, LLC) over 4 years ago

Jay, I say the hell with the HOA--get the rules changed to fit with the way things work.  Algae is normal---let it be---like the Beatles said.  It irks me when we make rules to address cosmetic issues and cost people money, time and potentially harm the environment.  To me roofs do not look normal if they do not have algae on them

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) over 4 years ago

We all got our ding notices.  Threats and all.  I even shared my formula with the HOA to put on the website, but they didn't.  After all was said and done, there are still maybe 150 houses with the algae!  The threats only worked on some, but not all!

Posted by Jay Markanich, Home Inspector - servicing all Northern Virginia (Jay Markanich Real Estate Inspections, LLC) over 4 years ago

We know that aesthetics trumps function and good sense almost every time 

Posted by James Quarello, Connecticut Home Inspector (JRV Home Inspection Services, LLC) over 4 years ago

Jay, I still sing, "Let it Be...."

Jim, for sure---every time.

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) over 4 years ago

Charles your video looks like the worker is adding years of wear in seconds. How could anyone see the need to spend time or money on such a thing? I don't get it.

Very good post, I saw the re-blog from WWW.

Posted by Noah Seidenberg, Chicagoland and Suburbs (800) 858-7917 (Coldwell Banker) over 4 years ago

Noah, when you watch both methods of cleaning you kind of have to wonder how anyone could think this is a good idea.

Posted by Charles Buell, Seattle Home Inspector (Charles Buell Inspections Inc.) over 4 years ago

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