Something occurred to me while pretreating a driveway. For those of you that do roofs or pretreat pretty hard, when it dries before rinsing, does that mean the bleach and chlorine specifically has finished it’s chemical action?
If you rinse the dried bleach off will it still have a risk of killing plants or is that over by that point?
I always post-treat so I can’t speak from experience, but for roofs no just because it dries does not mean you’re safe. In Florida a big problem we have is dew the next morning.
For example I wash a roof at 9am, the roof dries and has all day in the sun, the next morning dew forms on the roof, collects and drips to the ground… you can have damaged or dead plants at the roofline or downspouts. For this reason, I rinse usually the bottom 1/3 of a roof to be safe.
One possible mitigating factor with your pre-treating is the amount of water in the washing process would dillute the sh below the point of damaging plants. Just a thought.
Oh ok, so it can ‘reactivate’ when it gets wet again. That’s what I was curious about, didn’t know if the chlorine expended itself.
Look at the SH data sheets, they will tell you if it’s reactive
Good question
So I might be wrong, but the first word in SH is sodium, or salt. SH might not have the same potency after drying, but it will leave a salt residue, I imagine after rain it would be like saltwater. As long as it’s diluted enough should do no plant damage.
I have read that chlorine is deactivated by sunlight. I am just guessing but I doubt it gets reactivated by rehydration.
I was taught that you keep it wet to keep it active.
That’s what she said ;>)
