well as you all know that the east coast is getting lots and well lots of snow! and i see home owner putting deicer granules on there shingles to try to melt off the ice build up. This spring I've got a few houses to start cleaning and i'm concern if there will be a reaction with chlorine and salt granules. what signs should i see if there is any reactions. Or is asphalt shingles tough enough to handle these chemical elements....?