Chloras has to be used with care and all plant life should be pre-wet and rinsed again with tap water after cleaning to prevent leaves from burning. It has no adverse effects on glass, plastic, PVC, cement, stone, paint etc etc though.
It is the standard chem for roof cleaning & gutter whitening in the USA, and those guys even add extra's too it to make it more potent like Borax (Prevents algae regrowth) and Trisodium Phosphate (Boosts the bleaching power) as well as foaming agents and degreasers.