These customers would have been wise to have us or another contractor provide regular maintenance of their outdoor areas to avoid such a large build up of algae and acid rain. We were able to make their spaces look as good as new and fresh but at a higher cost. Plan power washing as a regular annual maintenance item so that you can enjoy your outdoor spaces free of nasty allergans and unsightly dirt.  There is no reason to feel like you are in the rainforest on your own back deck or patio. Team Hallco can help you get freshened up.