Hi,
We just got a call for a flat gravel roof clean . They want the surface moss to be removed . The measurements are 400’x 360’
… We have never done one of these jobs , does anyone have any suggestions on how to price it / execute the work ?
( lots off carpeted moss patches… )
Thanks.
My suggestion is to treat with SH and let it weather away naturally. I’ve seen moss completely fall away from roofs and surfaces 6 months after treatment.
We have tons of moss here in Portland - it grows on everything. I have a client with asphalt driveway and they were used to “pressure washing the moss off” every year - tedious and damaging, not to mention it didn’t treat the problem.
The wife asked if I could clean it and I offered to treat half of the drive that leads to the house with my SH roof wash (12% chlorine at 3:1). Spray and pay. It all turned white and was breaking up before I left. I came back 6 months later to pressure wash the metal roof and the moss was gone completely. I asked the husband how he felt the driveway/moss situation went. His reply, “It didn’t work out as I had expected.” I didn’t ask anything else, I felt nervous and a bit ashamed that I didn’t “make the client happy.”
I came back 15 months after treatment to clean their windows and looking out again at their drive I said to the husband, “Last time I was here I asked how the moss treatment went. You said, ‘It didn’t work out as I had expected,’ but as I look out, the moss is still gone. Did you do anything else to clean the moss up, pressure wash or treat the areas?”
His reply, “No, I just thought it was a light winter and it didn’t grow back as aggressively.”
My reply, “Actually, what happened is that we finally treated the moss down to the root level, killing it completely instead of just removing the top layer and leaving the roots behind and spread moss to grow back more aggressively.”
They had me back this week to treat the rest of their drive concluding that the treatment is what really kept their drive in good order.
