How I wanna be a PP Pro
Join Date: Oct 2012
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Normally if that roof has a fine layer of lichens than the roof will definitely need to have them removed. If it's been an ongoing problem than the roots will eat into the roof decking and then you might as well replace all roof and decking since it's near impossible to get rid of.
Those zink strips seem to work for the areas a few rows below the run where it's installed. I "think" the metal leaches off in rain and runs down roof where it creates a barrier?
If you clean that roof be sure to use a nontoxic cleaner, not bleach, that won't kill the vegetation. I saw a roof, and siding, that we had bid to powerwash and obviously we never won the bid (commercial apartment complex buildings) and the numb nut who won the bid killed all the bushes and the grass 10' around each building.