UPDATE 9/21/2021
FORGET ‘SPRAY AND FORGET’
Their hose-end sprayer is no longer refillable! At $35, it’s the most expensive 600 square feet you’ll treat! Buy ‘Wet and Forget’ instead!
From the response since the last Board meeting, here’s the details on how to get those nasty stains off your roof. The product I’ve used is “Spray and Forget” sprayandforget.com. There are others, such as “Wet and Forget”. In any case, here’s the drill.
For many homes, the hose-end sprayer will reach all of the roof from the ground. I haven’t used the hose end sprayer because my roof is too high. So I rigged up the pressure washer to do the job.
The key is to get a ‘Second Story nozzle. About $10 online for the pair, one for spraying, one for rinsing (which you don’t need for this project). These lower the pressure enough to make it safe to use on your shingles, but launches a stream of water high enough to reach the roof of most second story homes. I use at 2800 psi gas-powered job. I’ve heard that a machine as low as 1700 will do. Next, the mixing valves on most washers that allows you to add a chemical to your spray, is fixed from the factory, and can’t be adjusted. Spray and Forget uses a quirky 5 parts water to 1 part concentrate.
So, you need an adjustable mixing valve. The one that comes with your washer is almost always fixed at a rate for soap, which is wrong for Spray and Forget. So forget it. For about $20 online, the adjustable will allow you to get the quirky 5:1 ratio that’s required for this product.
Finally, and this may not be needed unless you have to really reach out and touch the peaks of a very high roof, go over to Zach’s across from Winn-Dixie and get an extension for your washer gun, 6′ or 8′, depending. This makes it really fun:
Spray and Forget changes the chemical structure of the shingles so the bad stuff can’t grow. Do this in the spring or summer. It takes a few months to really work. though you’ll see something start to happen in about a month. After a few years, do it again whether it needs it or not, that helps the roof stay clean. Important: wet down any plants or grass directly in the path of runoff before you start, and again when you’re done.
NOTE: This is not a paid endorsement; magnoliaresidents.com has not received any compensation, consideration or free cookies for this post. No animals have been harmed in preparing this article or print, or before or after the spraying process.